{
 "instance": {
  "altr-20221231.htm": {
   "axisCustom": 0,
   "axisStandard": 36,
   "baseTaxonomies": {
    "http://fasb.org/us-gaap/2022": 1375,
    "http://xbrl.sec.gov/dei/2022": 38
   },
   "contextCount": 402,
   "dts": {
    "calculationLink": {
     "local": [
      "altr-20221231_cal.xml"
     ]
    },
    "definitionLink": {
     "local": [
      "altr-20221231_def.xml"
     ]
    },
    "inline": {
     "local": [
      "altr-20221231.htm"
     ]
    },
    "labelLink": {
     "local": [
      "altr-20221231_lab.xml"
     ]
    },
    "presentationLink": {
     "local": [
      "altr-20221231_pre.xml"
     ]
    },
    "schema": {
     "local": [
      "altr-20221231.xsd"
     ],
     "remote": [
      "http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xl-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xlink-2003-12-31.xsd",
      "http://www.xbrl.org/2005/xbrldt-2005.xsd",
      "http://www.xbrl.org/2006/ref-2006-02-27.xsd",
      "http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd",
      "http://www.xbrl.org/lrr/role/reference-2009-12-16.xsd",
      "https://www.xbrl.org/2020/extensible-enumerations-2.0.xsd",
      "https://www.xbrl.org/dtr/type/2020-01-21/types.xsd",
      "https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd",
      "https://xbrl.fasb.org/srt/2022/elts/srt-roles-2022.xsd",
      "https://xbrl.fasb.org/srt/2022/elts/srt-types-2022.xsd",
      "https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd",
      "https://xbrl.fasb.org/us-gaap/2022/elts/us-roles-2022.xsd",
      "https://xbrl.fasb.org/us-gaap/2022/elts/us-types-2022.xsd",
      "https://xbrl.sec.gov/country/2022/country-2022.xsd",
      "https://xbrl.sec.gov/dei/2022/dei-2022.xsd"
     ]
    }
   },
   "elementCount": 880,
   "entityCount": 1,
   "hidden": {
    "http://fasb.org/us-gaap/2022": 16,
    "http://xbrl.sec.gov/dei/2022": 4,
    "total": 20
   },
   "keyCustom": 85,
   "keyStandard": 470,
   "memberCustom": 51,
   "memberStandard": 56,
   "nsprefix": "altr",
   "nsuri": "http://www.altair.com/20221231",
   "report": {
    "R1": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "dei:DocumentType",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "document",
     "isDefault": "true",
     "longName": "100000 - Document - Document and Entity Information",
     "menuCat": "Cover",
     "order": "1",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation",
     "shortName": "Document and Entity Information",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "dei:DocumentType",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R10": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SignificantAccountingPoliciesTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100090 - Disclosure - Summary of Significant Accounting Policies",
     "menuCat": "Notes",
     "order": "10",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies",
     "shortName": "Summary of Significant Accounting Policies",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SignificantAccountingPoliciesTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R11": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:RevenueFromContractWithCustomerTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100100 - Disclosure - Revenue from Contracts with Customers",
     "menuCat": "Notes",
     "order": "11",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomers",
     "shortName": "Revenue from Contracts with Customers",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:RevenueFromContractWithCustomerTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R12": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:BusinessCombinationDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100110 - Disclosure - Acquisitions",
     "menuCat": "Notes",
     "order": "12",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitions",
     "shortName": "Acquisitions",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:BusinessCombinationDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R13": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "altr:SupplementaryInformationTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100120 - Disclosure - Supplementary Information",
     "menuCat": "Notes",
     "order": "13",
     "role": "http://www.altair.com/20221231/taxonomy/role/DisclosureSupplementaryInformation1",
     "shortName": "Supplementary Information",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "altr:SupplementaryInformationTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R14": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100130 - Disclosure - Goodwill and Other Intangible Assets",
     "menuCat": "Notes",
     "order": "14",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssets",
     "shortName": "Goodwill and Other Intangible Assets",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R15": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DebtDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100140 - Disclosure - Debt",
     "menuCat": "Notes",
     "order": "15",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebt",
     "shortName": "Debt",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DebtDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R16": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100150 - Disclosure - Leases",
     "menuCat": "Notes",
     "order": "16",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeases",
     "shortName": "Leases",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R17": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:FairValueDisclosuresTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100160 - Disclosure - Fair Value Measurements",
     "menuCat": "Notes",
     "order": "17",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurements",
     "shortName": "Fair Value Measurements",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:FairValueDisclosuresTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R18": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:StockholdersEquityNoteDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100170 - Disclosure - Stockholders' Equity",
     "menuCat": "Notes",
     "order": "18",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquity",
     "shortName": "Stockholders' Equity",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:StockholdersEquityNoteDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R19": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100180 - Disclosure - Stock-Based Compensation",
     "menuCat": "Notes",
     "order": "19",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensation",
     "shortName": "Stock-Based Compensation",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R2": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CashAndCashEquivalentsAtCarryingValue",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "100010 - Statement - Consolidated Balance Sheets",
     "menuCat": "Statements",
     "order": "2",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets",
     "shortName": "Consolidated Balance Sheets",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:PrepaidExpenseAndOtherAssetsCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R20": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:IncomeTaxDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100190 - Disclosure - Income Taxes",
     "menuCat": "Notes",
     "order": "20",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxes",
     "shortName": "Income Taxes",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:IncomeTaxDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R21": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:EarningsPerShareTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100200 - Disclosure - Net Loss Per Share",
     "menuCat": "Notes",
     "order": "21",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShare",
     "shortName": "Net Loss Per Share",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:EarningsPerShareTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R22": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100210 - Disclosure - Retirement Benefits",
     "menuCat": "Notes",
     "order": "22",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefits",
     "shortName": "Retirement Benefits",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R23": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ComprehensiveIncomeNoteTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100220 - Disclosure - Accumulated Other Comprehensive Loss",
     "menuCat": "Notes",
     "order": "23",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLoss",
     "shortName": "Accumulated Other Comprehensive Loss",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ComprehensiveIncomeNoteTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R24": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100230 - Disclosure - Commitments and Contingencies",
     "menuCat": "Notes",
     "order": "24",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingencies",
     "shortName": "Commitments and Contingencies",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R25": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SegmentReportingDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100240 - Disclosure - Segment Information",
     "menuCat": "Notes",
     "order": "25",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformation",
     "shortName": "Segment Information",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SegmentReportingDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R26": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:SignificantAccountingPoliciesTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ConsolidationPolicyTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100260 - Disclosure - Summary of Significant Accounting Policies (Policies)",
     "menuCat": "Policies",
     "order": "26",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies",
     "shortName": "Summary of Significant Accounting Policies (Policies)",
     "subGroupType": "policies",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:SignificantAccountingPoliciesTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ConsolidationPolicyTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R27": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:RevenueFromContractWithCustomerTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DisaggregationOfRevenueTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100270 - Disclosure - Revenue from Contracts with Customers (Tables)",
     "menuCat": "Tables",
     "order": "27",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersTables",
     "shortName": "Revenue from Contracts with Customers (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:RevenueFromContractWithCustomerTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DisaggregationOfRevenueTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R28": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:BusinessCombinationDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_15079aaf-0ba0-41b6-b81b-c0ce69f3ac45",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100280 - Disclosure - Acquisitions (Tables)",
     "menuCat": "Tables",
     "order": "28",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables",
     "shortName": "Acquisitions (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:BusinessCombinationDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_15079aaf-0ba0-41b6-b81b-c0ce69f3ac45",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R29": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfRestrictedCashAndCashEquivalentsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100290 - Disclosure - Supplementary Information (Tables)",
     "menuCat": "Tables",
     "order": "29",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables",
     "shortName": "Supplementary Information (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfRestrictedCashAndCashEquivalentsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R3": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:PreferredStockParOrStatedValuePerShare",
      "reportCount": 1,
      "unitRef": "U_UnitedStatesOfAmericaDollarsShare",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "100020 - Statement - Consolidated Balance Sheets (Parenthetical)",
     "menuCat": "Statements",
     "order": "3",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical",
     "shortName": "Consolidated Balance Sheets (Parenthetical)",
     "subGroupType": "parenthetical",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_1de3947d-cd2e-483b-9a0a-34d4faee782c",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:CommonStockSharesIssued",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_shares",
      "xsiNil": "false"
     }
    },
    "R30": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfGoodwillTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100300 - Disclosure - Goodwill and Other Intangible Assets (Tables)",
     "menuCat": "Tables",
     "order": "30",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsTables",
     "shortName": "Goodwill and Other Intangible Assets (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfGoodwillTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R31": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:DebtDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ConvertibleDebtTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100310 - Disclosure - Debt (Tables)",
     "menuCat": "Tables",
     "order": "31",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtTables",
     "shortName": "Debt (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:DebtDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ConvertibleDebtTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R32": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:LeaseCostTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100320 - Disclosure - Leases (Tables)",
     "menuCat": "Tables",
     "order": "32",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesTables",
     "shortName": "Leases (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:LeaseCostTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R33": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100330 - Disclosure - Stock-Based Compensation (Tables)",
     "menuCat": "Tables",
     "order": "33",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables",
     "shortName": "Stock-Based Compensation (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R34": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100340 - Disclosure - Income Taxes (Tables)",
     "menuCat": "Tables",
     "order": "34",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesTables",
     "shortName": "Income Taxes (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R35": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:EarningsPerShareTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100350 - Disclosure - Net Loss Per Share (Tables)",
     "menuCat": "Tables",
     "order": "35",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareTables",
     "shortName": "Net Loss Per Share (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:EarningsPerShareTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R36": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100360 - Disclosure - Retirement Benefits (Tables)",
     "menuCat": "Tables",
     "order": "36",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsTables",
     "shortName": "Retirement Benefits (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R37": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:ComprehensiveIncomeNoteTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100370 - Disclosure - Accumulated Other Comprehensive Loss (Tables)",
     "menuCat": "Tables",
     "order": "37",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossTables",
     "shortName": "Accumulated Other Comprehensive Loss (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:ComprehensiveIncomeNoteTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R38": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:UnrecordedUnconditionalPurchaseObligationsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100380 - Disclosure - Commitments and Contingencies (Tables)",
     "menuCat": "Tables",
     "order": "38",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesTables",
     "shortName": "Commitments and Contingencies (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:UnrecordedUnconditionalPurchaseObligationsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R39": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfSegmentReportingInformationBySegmentTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100390 - Disclosure - Segment Information (Tables)",
     "menuCat": "Tables",
     "order": "39",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationTables",
     "shortName": "Segment Information (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfSegmentReportingInformationBySegmentTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R4": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "100030 - Statement - Consolidated Statements of Operations",
     "menuCat": "Statements",
     "order": "4",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations",
     "shortName": "Consolidated Statements of Operations",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:CostOfGoodsAndServicesSold",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R40": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock",
       "div",
       "us-gaap:SignificantAccountingPoliciesTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:AssetImpairmentCharges",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100400 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "40",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
     "shortName": "Summary of Significant Accounting Policies - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock",
       "div",
       "us-gaap:SignificantAccountingPoliciesTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:AssetImpairmentCharges",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R41": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100410 - Disclosure - Revenue from Contracts with Customers - Schedule of Disaggregation of Revenue (Detail)",
     "menuCat": "Details",
     "order": "41",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail",
     "shortName": "Revenue from Contracts with Customers - Schedule of Disaggregation of Revenue (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:DisaggregationOfRevenueTableTextBlock",
       "div",
       "us-gaap:RevenueFromContractWithCustomerTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_4b736166-7ec9-4513-807b-a01648471181",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R42": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100420 - Disclosure - Revenue from Contracts with Customers - Schedule of Disaggregation of Revenue (Parenthetical) (Detail)",
     "menuCat": "Details",
     "order": "42",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueParentheticalDetail",
     "shortName": "Revenue from Contracts with Customers - Schedule of Disaggregation of Revenue (Parenthetical) (Detail)",
     "subGroupType": "parenthetical",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "div",
       "us-gaap:DisaggregationOfRevenueTableTextBlock",
       "div",
       "us-gaap:RevenueFromContractWithCustomerTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_f3cdd2b0-c92a-4b81-9ed9-8c4f203a4151",
      "decimals": "-6",
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R43": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:RevenueFromContractWithCustomerTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "3",
      "first": true,
      "lang": null,
      "name": "altr:PercentageOfNetRevenuesThroughIndirectChannels",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100430 - Disclosure - Revenue from Contracts with Customers - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "43",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail",
     "shortName": "Revenue from Contracts with Customers - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:RevenueFromContractWithCustomerTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "3",
      "first": true,
      "lang": null,
      "name": "altr:PercentageOfNetRevenuesThroughIndirectChannels",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     }
    },
    "R44": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:RevenueFromContractWithCustomerTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_7225f8d9-2f10-4be3-81e4-d712ab527278",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100440 - Disclosure - Revenue from Contracts with Customers - Additional Information (Detail)1",
     "menuCat": "Details",
     "order": "44",
     "role": "http://www.altair.com/20221231/taxonomy/role/DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail1",
     "shortName": "Revenue from Contracts with Customers - Additional Information (Detail)1",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:RevenueFromContractWithCustomerTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_7225f8d9-2f10-4be3-81e4-d712ab527278",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R45": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:GainOnMarkToMarketAdjustmentOfContingentConsideration",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100450 - Disclosure - Acquisitions - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "45",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
     "shortName": "Acquisitions - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:BusinessCombinationDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_5b135774-7415-4756-831a-bc7d722b3602",
      "decimals": "2",
      "lang": null,
      "name": "us-gaap:BusinessAcquisitionPercentageOfVotingInterestsAcquired",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     }
    },
    "R46": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_64ef2aff-a1b0-4c03-a493-3f2ae8885dde",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DeferredTaxAssetsNet",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100460 - Disclosure - Acquisitions - Summary of Amounts of Identified Assets Acquired and Liabilities Assumed at the Acquisition Date (Detail)",
     "menuCat": "Details",
     "order": "46",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
     "shortName": "Acquisitions - Summary of Amounts of Identified Assets Acquired and Liabilities Assumed at the Acquisition Date (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "us-gaap:BusinessCombinationDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_ec911e2c-7b31-4e57-99c7-e97b14c8e263",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R47": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "div",
       "ix:continuation",
       "div",
       "us-gaap:BusinessCombinationDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_ec911e2c-7b31-4e57-99c7-e97b14c8e263",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100470 - Disclosure - Acquisitions - Summary of Amounts of Identified Assets Acquired and Liabilities Assumed at the Acquisition Date (Parenthetical) (Detail)",
     "menuCat": "Details",
     "order": "47",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
     "shortName": "Acquisitions - Summary of Amounts of Identified Assets Acquired and Liabilities Assumed at the Acquisition Date (Parenthetical) (Detail)",
     "subGroupType": "parenthetical",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "div",
       "ix:continuation",
       "div",
       "us-gaap:BusinessCombinationDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_ec911e2c-7b31-4e57-99c7-e97b14c8e263",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R48": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CashAndCashEquivalentsAtCarryingValue",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100480 - Disclosure - Supplementary Information - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail)",
     "menuCat": "Details",
     "order": "48",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetail",
     "shortName": "Supplementary Information - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:RestrictedCashAndCashEquivalentsNoncurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R49": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:AccountsReceivableAllowanceForCreditLossTableTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:AccountsReceivableTradeNetCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100490 - Disclosure - Supplementary Information - Schedule of Accounts Receivable Net (Detail)",
     "menuCat": "Details",
     "order": "49",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfAccountsReceivableNetDetail",
     "shortName": "Supplementary Information - Schedule of Accounts Receivable Net (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:AccountsReceivableAllowanceForCreditLossTableTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:AccountsReceivableTradeNetCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R5": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:NetIncomeLoss",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "100040 - Statement - Consolidated Statements of Comprehensive (Loss) Income",
     "menuCat": "Statements",
     "order": "5",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome",
     "shortName": "Consolidated Statements of Comprehensive (Loss) Income",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:ComprehensiveIncomeNetOfTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R50": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100500 - Disclosure - Supplementary Information - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "50",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail",
     "shortName": "Supplementary Information - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-5",
      "lang": null,
      "name": "us-gaap:Depreciation",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R51": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_64ef2aff-a1b0-4c03-a493-3f2ae8885dde",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100510 - Disclosure - Supplementary Information - Schedule of Provision for Credit Loss (Detail)",
     "menuCat": "Details",
     "order": "51",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail",
     "shortName": "Supplementary Information - Schedule of Provision for Credit Loss (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:ProvisionForDoubtfulAccounts",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R52": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:PropertyPlantAndEquipmentTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PropertyPlantAndEquipmentGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100520 - Disclosure - Supplementary Information - Summary of Property and Equipment (Detail)",
     "menuCat": "Details",
     "order": "52",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
     "shortName": "Supplementary Information - Summary of Property and Equipment (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:PropertyPlantAndEquipmentTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PropertyPlantAndEquipmentGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R53": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "div",
       "us-gaap:PropertyPlantAndEquipmentTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_ead62ea4-9957-4acd-b861-dffd681adb15",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:PropertyPlantAndEquipmentUsefulLife",
      "reportCount": 1,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100530 - Disclosure - Supplementary Information - Summary of Property and Equipment (Parenthetical) (Detail)",
     "menuCat": "Details",
     "order": "53",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail",
     "shortName": "Supplementary Information - Summary of Property and Equipment (Parenthetical) (Detail)",
     "subGroupType": "parenthetical",
     "uniqueAnchor": null
    },
    "R54": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:OtherCurrentLiabilitiesTableTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:AccruedObligationsForAcquisitionOfBusinesses",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100540 - Disclosure - Supplementary Information - Summary of Other Accrued Expenses and Current Liabilities (Detail)",
     "menuCat": "Details",
     "order": "54",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail",
     "shortName": "Supplementary Information - Summary of Other Accrued Expenses and Current Liabilities (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:OtherCurrentLiabilitiesTableTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:AccruedObligationsForAcquisitionOfBusinesses",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R55": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:OtherNoncurrentLiabilitiesTableTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DeferredIncomeTaxLiabilitiesNet",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100550 - Disclosure - Supplementary Information - Summary of Other Long-term Liabilities (Detail)",
     "menuCat": "Details",
     "order": "55",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail",
     "shortName": "Supplementary Information - Summary of Other Long-term Liabilities (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:OtherNoncurrentLiabilitiesTableTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DeferredIncomeTaxLiabilitiesNet",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R56": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:ExpenseOnRepurchaseOfConvertibleSeniorNote",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100560 - Disclosure - Supplementary Information - Schedule of Other Expense (Income), Net (Detail)",
     "menuCat": "Details",
     "order": "56",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail",
     "shortName": "Supplementary Information - Schedule of Other Expense (Income), Net (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock",
       "div",
       "altr:SupplementaryInformationTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:ForeignCurrencyTransactionGainLossBeforeTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R57": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_64ef2aff-a1b0-4c03-a493-3f2ae8885dde",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:Goodwill",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100570 - Disclosure - Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill Attributable to Software Reportable Segment (Detail)",
     "menuCat": "Details",
     "order": "57",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsChangesInCarryingAmountOfGoodwillAttributableToSoftwareReportableSegmentDetail",
     "shortName": "Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill Attributable to Software Reportable Segment (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfGoodwillTextBlock",
       "div",
       "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:GoodwillAcquiredDuringPeriod",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R58": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "altr:ScheduleOfOtherIntangibleAssetsTableTextBlock",
       "div",
       "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:FiniteLivedIntangibleAssetsGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100580 - Disclosure - Goodwill and Other Intangible Assets - Schedule of Other Intangible Assets (Detail)",
     "menuCat": "Details",
     "order": "58",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail",
     "shortName": "Goodwill and Other Intangible Assets - Schedule of Other Intangible Assets (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "altr:ScheduleOfOtherIntangibleAssetsTableTextBlock",
       "div",
       "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:FiniteLivedIntangibleAssetsGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R59": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AmortizationOfIntangibleAssets",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100590 - Disclosure - Goodwill and Other Intangible Assets - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "59",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsAdditionalInformationDetail",
     "shortName": "Goodwill and Other Intangible Assets - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R6": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "100050 - Statement - Consolidated Statements of Comprehensive (Loss) Income (Parenthetical)",
     "menuCat": "Statements",
     "order": "6",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncomeParenthetical",
     "shortName": "Consolidated Statements of Comprehensive (Loss) Income (Parenthetical)",
     "subGroupType": "parenthetical",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R60": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock",
       "div",
       "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100600 - Disclosure - Goodwill and Other Intangible Assets - Summary of Estimated Amortization Expense (Detail)",
     "menuCat": "Details",
     "order": "60",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail",
     "shortName": "Goodwill and Other Intangible Assets - Summary of Estimated Amortization Expense (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock",
       "div",
       "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R61": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RetainedEarningsAccumulatedDeficit",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100610 - Disclosure - Debt - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "61",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
     "shortName": "Debt - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "us-gaap:LineOfCredit",
       "span",
       "p",
       "us-gaap:DebtDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_1eb37454-a9ea-40a6-ad34-7c19eeea249c",
      "decimals": "INF",
      "lang": null,
      "name": "us-gaap:LineOfCredit",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R62": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:ConvertibleNotesPayableCurrent",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100620 - Disclosure - Debt - Schedule of Net Carrying Value of Liability Component of 2027 and 2024 Notes (Detail)",
     "menuCat": "Details",
     "order": "62",
     "role": "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
     "shortName": "Debt - Schedule of Net Carrying Value of Liability Component of 2027 and 2024 Notes (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ConvertibleDebtTableTextBlock",
       "div",
       "us-gaap:DebtDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_604d689e-f008-4658-87c0-058d9e2eb946",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:DebtInstrumentCarryingAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R63": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AmortizationOfFinancingCostsAndDiscounts",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100630 - Disclosure - Debt - Schedule of Interest Expense Related to 2027 and 2024 Notes (Detail)",
     "menuCat": "Details",
     "order": "63",
     "role": "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail",
     "shortName": "Debt - Schedule of Interest Expense Related to 2027 and 2024 Notes (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:InterestIncomeAndInterestExpenseDisclosureTableTextBlock",
       "div",
       "us-gaap:DebtDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_4152c5dc-0559-493e-becd-fb87b03f470f",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:InterestExpenseDebtExcludingAmortization",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R64": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100640 - Disclosure - Leases - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "64",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail",
     "shortName": "Leases - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R65": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:LeaseCostTableTextBlock",
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseCost",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100650 - Disclosure - Leases - Schedule of Components of Lease Cost (Detail)",
     "menuCat": "Details",
     "order": "65",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail",
     "shortName": "Leases - Schedule of Components of Lease Cost (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:LeaseCostTableTextBlock",
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseCost",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R66": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseRightOfUseAsset",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100660 - Disclosure - Leases - Schedule of Supplemental Balance Sheet Information Related to Lease Liabilities (Detail)",
     "menuCat": "Details",
     "order": "66",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail",
     "shortName": "Leases - Schedule of Supplemental Balance Sheet Information Related to Lease Liabilities (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "altr:ScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesTableTextBlock",
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": null,
      "lang": "en-US",
      "name": "us-gaap:OperatingLeaseWeightedAverageRemainingLeaseTerm1",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R67": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "altr:ScheduleOfSupplementalCashFlowInformationRelatedToLeasesTableTextBlock",
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeasePayments",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100670 - Disclosure - Leases - Schedule of Supplemental Cash Flow Information Related to Leases (Detail)",
     "menuCat": "Details",
     "order": "67",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalCashFlowInformationRelatedToLeasesDetail",
     "shortName": "Leases - Schedule of Supplemental Cash Flow Information Related to Leases (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "altr:ScheduleOfSupplementalCashFlowInformationRelatedToLeasesTableTextBlock",
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeasePayments",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R68": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock",
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100680 - Disclosure - Leases - Schedule of Maturities of Operating Lease Liabilities (Detail)",
     "menuCat": "Details",
     "order": "68",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail",
     "shortName": "Leases - Schedule of Maturities of Operating Lease Liabilities (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock",
       "div",
       "altr:LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R69": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:FairValueDisclosuresTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_c2a3878b-67b1-41ce-842d-21903d5c824c",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:ConvertibleDebtFairValueDisclosures",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100690 - Disclosure - Fair Value Measurements - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "69",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail",
     "shortName": "Fair Value Measurements - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:FairValueDisclosuresTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_c2a3878b-67b1-41ce-842d-21903d5c824c",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:ConvertibleDebtFairValueDisclosures",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R7": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_904822bd-8b66-4b72-a5d6-03db01178a1a",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:StockholdersEquity",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "100060 - Statement - Consolidated Statement of Changes in Stockholders' Equity (Deficit)",
     "menuCat": "Statements",
     "order": "7",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit",
     "shortName": "Consolidated Statement of Changes in Stockholders' Equity (Deficit)",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_6ed139e5-62eb-42bb-9de2-b6ee424d350c",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:StockholdersEquity",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R70": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:StockholdersEquityNoteDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:PreferredStockSharesAuthorized",
      "reportCount": 1,
      "unitRef": "U_shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100710 - Disclosure - Stockholders' Equity - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "70",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
     "shortName": "Stockholders' Equity - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:StockholdersEquityNoteDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "INF",
      "lang": null,
      "name": "us-gaap:CommonStockDividendsPerShareDeclared",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_UnitedStatesOfAmericaDollarsShare",
      "xsiNil": "false"
     }
    },
    "R71": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_902b2014-3349-4ba6-96eb-652ffe7da8eb",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:AllocatedShareBasedCompensationExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100720 - Disclosure - Stock-based Compensation - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "71",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
     "shortName": "Stock-based Compensation - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_902b2014-3349-4ba6-96eb-652ffe7da8eb",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:AllocatedShareBasedCompensationExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R72": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_c2df59dc-1581-477f-9b02-5eee90b7eb44",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber",
      "reportCount": 1,
      "unitRef": "U_shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100730 - Disclosure - Stock-based Compensation - Summary of Stock Option Activity under NSO Plan (Detail)",
     "menuCat": "Details",
     "order": "72",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail",
     "shortName": "Stock-based Compensation - Summary of Stock Option Activity under NSO Plan (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_c89b5e92-ecc1-4862-a1ef-40786f09f837",
      "decimals": "INF",
      "lang": null,
      "name": "us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_shares",
      "xsiNil": "false"
     }
    },
    "R73": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_aa3ac485-7a53-43ec-8f60-8f5a4737186b",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber",
      "reportCount": 1,
      "unitRef": "U_shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100740 - Disclosure - Stock-based Compensation - Summary of Stock Option Activity under 2012 Plan (Detail)",
     "menuCat": "Details",
     "order": "73",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
     "shortName": "Stock-based Compensation - Summary of Stock Option Activity under 2012 Plan (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_4bc0e00e-f640-44bb-ae1e-a8ed0a56caaf",
      "decimals": "INF",
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_shares",
      "xsiNil": "false"
     }
    },
    "R74": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_282b2fad-e580-49c4-8d85-4f9430c5757e",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100750 - Disclosure - Stock-based Compensation - Summary of Restricted Stock Units Awarded (Detail)",
     "menuCat": "Details",
     "order": "74",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
     "shortName": "Stock-based Compensation - Summary of Restricted Stock Units Awarded (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_282b2fad-e580-49c4-8d85-4f9430c5757e",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_shares",
      "xsiNil": "false"
     }
    },
    "R75": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_c04f24cb-9905-4aac-810f-185320d16f5a",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber",
      "reportCount": 1,
      "unitRef": "U_shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100760 - Disclosure - Stock-based Compensation - Summary of Stock Option Activity under 2017 Plan (Detail)",
     "menuCat": "Details",
     "order": "75",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
     "shortName": "Stock-based Compensation - Summary of Stock Option Activity under 2017 Plan (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_18f6bfb5-fa9d-42cc-85e5-860823346a97",
      "decimals": "INF",
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_shares",
      "xsiNil": "false"
     }
    },
    "R76": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "2",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100770 - Disclosure - Stock-based Compensation - Summary of Fair value of Company's Stock Options Granted (Detail)",
     "menuCat": "Details",
     "order": "76",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail",
     "shortName": "Stock-based Compensation - Summary of Fair value of Company's Stock Options Granted (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "2",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     }
    },
    "R77": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensation",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100780 - Disclosure - Stock-based Compensation - Summary of Stock-Based Compensation Expense (Detail)",
     "menuCat": "Details",
     "order": "77",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail",
     "shortName": "Stock-based Compensation - Summary of Stock-Based Compensation Expense (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock",
       "div",
       "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_ab75cfef-669a-4f9e-b026-9ea81dc57de7",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:ShareBasedCompensation",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R78": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100790 - Disclosure - Income Taxes - Components of Income (Loss) Before Income Taxes (Detail)",
     "menuCat": "Details",
     "order": "78",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfIncomeLossBeforeIncomeTaxesDetail",
     "shortName": "Income Taxes - Components of Income (Loss) Before Income Taxes (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R79": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CurrentFederalTaxExpenseBenefit",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100800 - Disclosure - Income Taxes - Significant Components of Income Tax Expense (Detail)",
     "menuCat": "Details",
     "order": "79",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail",
     "shortName": "Income Taxes - Significant Components of Income Tax Expense (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CurrentFederalTaxExpenseBenefit",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R8": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:ProfitLoss",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "100070 - Statement - Consolidated Statements of Cash Flows",
     "menuCat": "Statements",
     "order": "8",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows",
     "shortName": "Consolidated Statements of Cash Flows",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:ProfitLoss",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R80": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate",
      "reportCount": 1,
      "unitRef": "U_pure",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100810 - Disclosure - Income Taxes - Reconciliation of Income Taxes Calculated at U.S. Federal Statutory Income Tax Rate (Detail)",
     "menuCat": "Details",
     "order": "80",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail",
     "shortName": "Income Taxes - Reconciliation of Income Taxes Calculated at U.S. Federal Statutory Income Tax Rate (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R81": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_5ec73a01-5635-4f5c-8fec-31bf237458d4",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "altr:TaxCutsAndJobsActOf2017ForeignIncomeExemptionCriteriaSubjectToCorporateTaxRateMinimumPercentage",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100820 - Disclosure - Income Taxes - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "81",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
     "shortName": "Income Taxes - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_5ec73a01-5635-4f5c-8fec-31bf237458d4",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "altr:TaxCutsAndJobsActOf2017ForeignIncomeExemptionCriteriaSubjectToCorporateTaxRateMinimumPercentage",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     }
    },
    "R82": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DeferredTaxAssetsDeferredIncome",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100830 - Disclosure - Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail)",
     "menuCat": "Details",
     "order": "82",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail",
     "shortName": "Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DeferredTaxAssetsDeferredIncome",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R83": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:SummaryOfValuationAllowanceTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_32e7720b-9f40-4b84-a14a-84fdfedad0bf",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:ValuationAllowancesAndReservesBalance",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100840 - Disclosure - Income Taxes - Summary of Changes to Valuation Allowance Balance (Detail)",
     "menuCat": "Details",
     "order": "83",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail",
     "shortName": "Income Taxes - Summary of Changes to Valuation Allowance Balance (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:SummaryOfValuationAllowanceTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_adb0fd08-455f-4114-837f-739da79fc3bd",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:ValuationAllowancesAndReservesBalance",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R84": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "altr:SummaryOfOperatingLossAndTaxCreditCarryForwardsTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "altr:OperatingLossCarryforwardsExpirationDateOne",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100850 - Disclosure - Income Taxes - Operating Loss and Tax Credit Carryforwards (Detail)",
     "menuCat": "Details",
     "order": "84",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail",
     "shortName": "Income Taxes - Operating Loss and Tax Credit Carryforwards (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "altr:SummaryOfOperatingLossAndTaxCreditCarryForwardsTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "altr:OperatingLossCarryforwardsExpirationDateOne",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R85": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_64ef2aff-a1b0-4c03-a493-3f2ae8885dde",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:UnrecognizedTaxBenefits",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100860 - Disclosure - Income Taxes - Reconciliation of Beginning and Ending Amounts of Unrecognized Tax Benefits (Detail)",
     "menuCat": "Details",
     "order": "85",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfBeginningAndEndingAmountsOfUnrecognizedTaxBenefitsDetail",
     "shortName": "Income Taxes - Reconciliation of Beginning and Ending Amounts of Unrecognized Tax Benefits (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock",
       "div",
       "us-gaap:IncomeTaxDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_904822bd-8b66-4b72-a5d6-03db01178a1a",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:UnrecognizedTaxBenefits",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R86": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:NetIncomeLoss",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100870 - Disclosure - Net Loss Per Share - Computation of Numerators and Denominators Used in Basic and Diluted Net (Loss) Income Per Share Amounts (Detail)",
     "menuCat": "Details",
     "order": "86",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail",
     "shortName": "Net Loss Per Share - Computation of Numerators and Denominators Used in Basic and Diluted Net (Loss) Income Per Share Amounts (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R87": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock",
       "div",
       "us-gaap:EarningsPerShareTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100880 - Disclosure - Net Loss Per Share - Schedule of Anti-dilutive Shares Excluded from Computation of Diluted Net Loss Per Share (Detail)",
     "menuCat": "Details",
     "order": "87",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntiDilutiveSharesExcludedFromComputationOfDilutedNetLossPerShareDetail",
     "shortName": "Net Loss Per Share - Schedule of Anti-dilutive Shares Excluded from Computation of Diluted Net Loss Per Share (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock",
       "div",
       "us-gaap:EarningsPerShareTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_shares",
      "xsiNil": "false"
     }
    },
    "R88": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "us-gaap:DebtInstrumentConvertibleTermsOfConversionFeature",
       "span",
       "p",
       "us-gaap:DebtDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_7202d974-98cd-4c9f-940c-130b6b51fb11",
      "decimals": "2",
      "first": true,
      "lang": null,
      "name": "us-gaap:DebtInstrumentConvertibleConversionPrice1",
      "reportCount": 1,
      "unitRef": "U_UnitedStatesOfAmericaDollarsShare",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100890 - Disclosure - Net Loss Per Share - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "88",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail",
     "shortName": "Net Loss Per Share - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R89": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "2",
      "first": true,
      "lang": null,
      "name": "us-gaap:DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100900 - Disclosure - Retirement Benefits - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "89",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsAdditionalInformationDetail",
     "shortName": "Retirement Benefits - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "2",
      "first": true,
      "lang": null,
      "name": "us-gaap:DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_pure",
      "xsiNil": "false"
     }
    },
    "R9": {
     "firstAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:NatureOfOperations",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100080 - Disclosure - Description of Business",
     "menuCat": "Notes",
     "order": "9",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDescriptionOfBusiness",
     "shortName": "Description of Business",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:NatureOfOperations",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R90": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock",
       "div",
       "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:DefinedBenefitPensionPlanAssetsNoncurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100910 - Disclosure - Retirement Benefits - Schedule of Pension Benefits Obligation (Detail)",
     "menuCat": "Details",
     "order": "90",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail",
     "shortName": "Retirement Benefits - Schedule of Pension Benefits Obligation (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock",
       "div",
       "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:DefinedBenefitPensionPlanAssetsNoncurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R91": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfExpectedBenefitPaymentsTableTextBlock",
       "div",
       "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100920 - Disclosure - Retirement Benefits - Schedule of Estimated Future Benefit Payments (Detail)",
     "menuCat": "Details",
     "order": "91",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfEstimatedFutureBenefitPaymentsDetail",
     "shortName": "Retirement Benefits - Schedule of Estimated Future Benefit Payments (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfExpectedBenefitPaymentsTableTextBlock",
       "div",
       "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R92": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_64ef2aff-a1b0-4c03-a493-3f2ae8885dde",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:StockholdersEquity",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100930 - Disclosure - Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss (Detail)",
     "menuCat": "Details",
     "order": "92",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail",
     "shortName": "Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock",
       "div",
       "us-gaap:ComprehensiveIncomeNoteTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R93": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_ccd954f9-4021-48b8-9e61-9712367a9ce5",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:RoyaltyExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100940 - Disclosure - Commitments and Contingencies - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "93",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail",
     "shortName": "Commitments and Contingencies - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_ccd954f9-4021-48b8-9e61-9712367a9ce5",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:RoyaltyExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R94": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PurchaseObligationDueInNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100950 - Disclosure - Commitments and Contingencies - Future Purchase Obligations (Details)",
     "menuCat": "Details",
     "order": "94",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails",
     "shortName": "Commitments and Contingencies - Future Purchase Obligations (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PurchaseObligationDueInNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R95": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:NumberOfReportableSegments",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_Segment",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100960 - Disclosure - Segment Information - Additional Information (Detail)",
     "menuCat": "Details",
     "order": "95",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail",
     "shortName": "Segment Information - Additional Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:NumberOfReportableSegments",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_Segment",
      "xsiNil": "false"
     }
    },
    "R96": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100970 - Disclosure - Segment Information - Schedule of Segment Reporting Information (Detail)",
     "menuCat": "Details",
     "order": "96",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail",
     "shortName": "Segment Information - Schedule of Segment Reporting Information (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfSegmentReportingInformationBySegmentTextBlock",
       "div",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_405cd490-b914-4593-968f-cd15586f1bf3",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R97": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfSegmentReportingInformationBySegmentTextBlock",
       "div",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "altr:AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100980 - Disclosure - Segment Information - Reconciliation of U.S. GAAP Income (Loss) Before Income Taxes to Adjusted EBITDA (Detail)",
     "menuCat": "Details",
     "order": "97",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail",
     "shortName": "Segment Information - Reconciliation of U.S. GAAP Income (Loss) Before Income Taxes to Adjusted EBITDA (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock",
       "div",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "lang": null,
      "name": "altr:InterestIncomeAndOther",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R98": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "ix:continuation",
       "span",
       "div",
       "div",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "altr:CurrencyLossesOnAcquisitionRelatedIntercompanyLoans",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "100990 - Disclosure - Segment Information - Reconciliation of U.S. GAAP Income (Loss) Before Income Taxes to Adjusted EBITDA (Parenthetical) (Detail)",
     "menuCat": "Details",
     "order": "98",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail",
     "shortName": "Segment Information - Reconciliation of U.S. GAAP Income (Loss) Before Income Taxes to Adjusted EBITDA (Parenthetical) (Detail)",
     "subGroupType": "parenthetical",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "ix:continuation",
       "span",
       "div",
       "div",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "altr:CurrencyLossesOnAcquisitionRelatedIntercompanyLoans",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    },
    "R99": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_d41e5149-fba0-491a-a2bb-728cce555a53",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unitRef": "U_USD",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "101000 - Disclosure - Segment Information - Summary of Sales to External Customers and Long-Lived Assets by Geographical Areas (Detail)",
     "menuCat": "Details",
     "order": "99",
     "role": "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail",
     "shortName": "Segment Information - Summary of Sales to External Customers and Long-Lived Assets by Geographical Areas (Detail)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "p",
       "td",
       "tr",
       "table",
       "us-gaap:ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock",
       "div",
       "us-gaap:SegmentReportingDisclosureTextBlock",
       "div",
       "body",
       "html"
      ],
      "baseRef": "altr-20221231.htm",
      "contextRef": "C_9f7d489e-f13f-4c19-8685-9a5ac7bc3339",
      "decimals": "-3",
      "lang": null,
      "name": "altr:LongLivedAssets",
      "reportCount": 1,
      "unique": true,
      "unitRef": "U_USD",
      "xsiNil": "false"
     }
    }
   },
   "segmentCount": 108,
   "tag": {
    "altr_ABRLoansMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A B R Loans.",
        "label": "A B R Loans [Member]",
        "terseLabel": "ABR Loans [Member]"
       }
      }
     },
     "localname": "ABRLoansMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_APRLoansMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "APR loans.",
        "label": "A P R Loans [Member]",
        "terseLabel": "APR Loans [Member]"
       }
      }
     },
     "localname": "APRLoansMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_AccountingPoliciesLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accounting policies.",
        "label": "Accounting Policies [Line Items]",
        "terseLabel": "Accounting Policies [Line Items]"
       }
      }
     },
     "localname": "AccountingPoliciesLineItems",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_AccountingPoliciesTable": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accounting policies.",
        "label": "Accounting Policies [Table]",
        "terseLabel": "Accounting Policies [Table]"
       }
      }
     },
     "localname": "AccountingPoliciesTable",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_AccountsReceivableNetCurrentMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accounts receivable net current.",
        "label": "Accounts Receivable Net Current [Member]",
        "terseLabel": "Accounts Receivable [Member]"
       }
      }
     },
     "localname": "AccountsReceivableNetCurrentMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_AccountsReceivableTradeNetCurrent": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfAccountsReceivableNetDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_AccountsReceivableNetCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accounts receivable, trade, net, current.",
        "label": "Accounts Receivable Trade Net Current",
        "terseLabel": "Accounts receivable, trade"
       }
      }
     },
     "localname": "AccountsReceivableTradeNetCurrent",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfAccountsReceivableNetDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AccruedDefinedContributionPlanLiabilitiesCurrent": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 8.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accrued defined contribution plan liabilities current.",
        "label": "Accrued Defined Contribution Plan Liabilities Current",
        "terseLabel": "Defined contribution plan liabilities"
       }
      }
     },
     "localname": "AccruedDefinedContributionPlanLiabilitiesCurrent",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AccruedEmployeeStockPurchasePlanContributionsCurrent": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accrued employee stock purchase plan contributions current.",
        "label": "Accrued Employee Stock Purchase Plan Contributions Current",
        "terseLabel": "Employee stock purchase plan obligations"
       }
      }
     },
     "localname": "AccruedEmployeeStockPurchasePlanContributionsCurrent",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AccruedObligationsForAcquisitionOfBusinesses": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accrued obligations for acquisition of businesses.",
        "label": "Accrued Obligations For Acquisition Of Businesses",
        "terseLabel": "Obligations related to acquisition of businesses"
       }
      }
     },
     "localname": "AccruedObligationsForAcquisitionOfBusinesses",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail": {
       "order": 0.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Adjusted earnings before interest taxes depreciation and amortization.",
        "label": "Adjusted Earnings Before Interest Taxes Depreciation And Amortization",
        "terseLabel": "Adjusted EBITDA"
       }
      }
     },
     "localname": "AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AllowanceForDoubtfulAccountsForeignCurrencyTranslationAdjustments": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Allowance For Doubtful Accounts Foreign Currency Translation Adjustments",
        "label": "Allowance For Doubtful Accounts Foreign Currency Translation Adjustments",
        "negatedLabel": "Effects of foreign currency translation"
       }
      }
     },
     "localname": "AllowanceForDoubtfulAccountsForeignCurrencyTranslationAdjustments",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AllowanceForDoubtfulAccountsReceivableWriteOffsNet": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Allowance For Doubtful Accounts Receivable Write Offs Net",
        "label": "Allowance For Doubtful Accounts Receivable Write Offs Net",
        "negatedLabel": "Write-off, net of recoveries"
       }
      }
     },
     "localname": "AllowanceForDoubtfulAccountsReceivableWriteOffsNet",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AmountOfEligibleCompensationForEmployeePayrollDeductions": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of eligible compensation for employee payroll deductions.",
        "label": "Amount Of Eligible Compensation For Employee Payroll Deductions",
        "terseLabel": "Amount of eligible compensation for employee payroll deductions"
       }
      }
     },
     "localname": "AmountOfEligibleCompensationForEmployeePayrollDeductions",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AmountWithheldOnBehalfOfEmployeesForFuturePurchase": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount withheld on behalf of employees for future purchase.",
        "label": "Amount Withheld On Behalf Of Employees For Future Purchase",
        "terseLabel": "Amount withheld on behalf of employees for a future purchase"
       }
      }
     },
     "localname": "AmountWithheldOnBehalfOfEmployeesForFuturePurchase",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_AssetsHeldForSalePolicyTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Assets Held For Sale [Policy Text Block]",
        "label": "Assets Held For Sale [Policy Text Block]",
        "terseLabel": "Assets held for sale"
       }
      }
     },
     "localname": "AssetsHeldForSalePolicyTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_BusinessCombinationEstimatedPostCombinationExpense": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Business combination estimated post combination expense.",
        "label": "Business Combination Estimated Post Combination Expense",
        "terseLabel": "Business combination, estimated post combination expense"
       }
      }
     },
     "localname": "BusinessCombinationEstimatedPostCombinationExpense",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSASLegalLiability": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 7.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Business combination recognized identifiable assets acquired and liabilities assumed sas legal liability.",
        "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed S A S Legal Liability",
        "negatedLabel": "SAS legal liability"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSASLegalLiability",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_CapitalizedResearchAndDevelopmentExpense": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Capitalized Research and Development Expense",
        "label": "Capitalized Research and Development Expense"
       }
      }
     },
     "localname": "CapitalizedResearchAndDevelopmentExpense",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_CashPaidForAmountsIncludedInMeasurementOfLeaseLiabilitiesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Cash paid for amounts included in measurement of lease liabilities.",
        "label": "Cash Paid For Amounts Included In Measurement Of Lease Liabilities [Abstract]",
        "terseLabel": "Cash paid for amounts included in the measurement of lease liabilities:"
       }
      }
     },
     "localname": "CashPaidForAmountsIncludedInMeasurementOfLeaseLiabilitiesAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalCashFlowInformationRelatedToLeasesDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_ClientEngineeringServicesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Client engineering services.",
        "label": "Client Engineering Services [Member]",
        "terseLabel": "Client Engineering Services [Member]"
       }
      }
     },
     "localname": "ClientEngineeringServicesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ClientEngineeringServicesSegmentMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Client engineering services.",
        "label": "Client Engineering Services Segment [Member]",
        "terseLabel": "CES [Member]",
        "verboseLabel": "CES [Member]"
       }
      }
     },
     "localname": "ClientEngineeringServicesSegmentMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_CommonStockNumberOfVotesPerShare": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Common Stock Number Of Votes Per Share",
        "label": "Common Stock Number Of Votes Per Share",
        "terseLabel": "Number of votes entitled per share"
       }
      }
     },
     "localname": "CommonStockNumberOfVotesPerShare",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "altr_ComputerEquipmentAndSoftwareMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Computer equipment and software.",
        "label": "Computer Equipment And Software [Member]",
        "terseLabel": "Computer Equipment and Software [Member]"
       }
      }
     },
     "localname": "ComputerEquipmentAndSoftwareMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ConceptEngineeringMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Concept Engineering member.",
        "label": "Concept Engineering [Member]",
        "terseLabel": "Concept Engineering [Member]"
       }
      }
     },
     "localname": "ConceptEngineeringMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ConvertibleNotesHoldersConversionRightsUnderCircumstancesOneMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Convertible notes, holders conversion rights under circumstances 1.",
        "label": "Convertible Notes Holders Conversion Rights Under Circumstances One [Member]",
        "terseLabel": "Convertible Notes, Holders Conversion Rights, Circumstances 1 [Member]"
       }
      }
     },
     "localname": "ConvertibleNotesHoldersConversionRightsUnderCircumstancesOneMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ConvertibleNotesHoldersConversionRightsUnderCircumstancesTwoMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Convertible notes holders conversion rights under circumstances two [Member]",
        "label": "Convertible Notes Holders Conversion Rights Under Circumstances Two [Member]",
        "terseLabel": "Convertible Notes, Holders Conversion Rights, Circumstances 2 [Member]"
       }
      }
     },
     "localname": "ConvertibleNotesHoldersConversionRightsUnderCircumstancesTwoMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ConvertibleSeniorNotesDueInTwoThousandTwentyFourAndTwoThousandTwentySevenMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Convertible Senior Notes Due In Two Thousand Twenty Four And Two Thousand Twenty Seven.",
        "label": "Convertible Senior Notes Due In Two Thousand Twenty Four And Two Thousand Twenty Seven [Member]",
        "terseLabel": "Convertible Senior Notes Due in 2024 and 2027 [Member]"
       }
      }
     },
     "localname": "ConvertibleSeniorNotesDueInTwoThousandTwentyFourAndTwoThousandTwentySevenMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ConvertibleSeniorNotesDueInTwoThousandTwentyFourMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Convertible senior notes due in two thousand twenty four.",
        "label": "Convertible Senior Notes Due In Two Thousand Twenty Four [Member]",
        "terseLabel": "Convertible Senior Notes Due in 2024 [Member]"
       }
      }
     },
     "localname": "ConvertibleSeniorNotesDueInTwoThousandTwentyFourMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ConvertibleSeniorNotesDueInTwoThousandTwentySevenMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Convertible senior notes due in two thousand twenty seven.",
        "label": "Convertible Senior Notes Due In Two Thousand Twenty Seven [Member]",
        "terseLabel": "Convertible senior notes due in 2027 [Member]"
       }
      }
     },
     "localname": "ConvertibleSeniorNotesDueInTwoThousandTwentySevenMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ConvertibleSharesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Convertible shares.",
        "label": "Convertible Shares [Member]",
        "terseLabel": "Convertible Shares [Member]"
       }
      }
     },
     "localname": "ConvertibleSharesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntiDilutiveSharesExcludedFromComputationOfDilutedNetLossPerShareDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_CurrencyGainsOnAcquisitionRelatedIntercompanyLoans": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Currency gains on acquisition related intercompany loans.",
        "label": "Currency Gains On Acquisition Related Intercompany Loans",
        "terseLabel": "Currency gains on acquisition-related intercompany loans"
       }
      }
     },
     "localname": "CurrencyGainsOnAcquisitionRelatedIntercompanyLoans",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_CurrencyLossesOnAcquisitionRelatedIntercompanyLoans": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Currency losses on acquisition related intercompany loans.",
        "label": "Currency Losses On Acquisition Related Intercompany Loans",
        "terseLabel": "Currency losses on acquisition-related intercompany loans"
       }
      }
     },
     "localname": "CurrencyLossesOnAcquisitionRelatedIntercompanyLoans",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_CurrentTaxExpenseBenefitAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Current tax expense benefit.",
        "label": "Current Tax Expense Benefit [Abstract]",
        "terseLabel": "Current"
       }
      }
     },
     "localname": "CurrentTaxExpenseBenefitAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_DebtInstrumentCommencementOfInterestDate": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Debt instrument commencement of interest date.",
        "label": "Debt Instrument Commencement Of Interest Date",
        "terseLabel": "Interest payment commencement date"
       }
      }
     },
     "localname": "DebtInstrumentCommencementOfInterestDate",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "dateItemType"
    },
    "altr_DebtInstrumentConvertibleConversionRatePrincipalAmount": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Debt instrument convertible conversion rate principal amount.",
        "label": "Debt Instrument Convertible Conversion Rate Principal Amount",
        "terseLabel": "Debt instrument conversion rate principal amount of notes"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleConversionRatePrincipalAmount",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_DebtInstrumentConvertibleThresholdBusinessDays": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Debt instrument convertible threshold business days.",
        "label": "Debt Instrument Convertible Threshold Business Days",
        "terseLabel": "Debt instrument, convertible, business days"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleThresholdBusinessDays",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "altr_DebtInstrumentConvertibleThresholdMaximumPercentageOfProductOfLastReportedSalePriceOfCommonStock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Debt instrument convertible threshold maximum percentage of product of last reported sale price of common stock.",
        "label": "Debt Instrument Convertible Threshold Maximum Percentage Of Product Of Last Reported Sale Price Of Common Stock",
        "terseLabel": "Debt instrument, convertible, maximum threshold percentage of sale price of common stock during measurement period"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleThresholdMaximumPercentageOfProductOfLastReportedSalePriceOfCommonStock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "altr_DebtInstrumentPrincipalOutstanding": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Debt instrument principal outstanding.",
        "label": "Debt Instrument Principal Outstanding",
        "terseLabel": "Debt instrument principal outstanding"
       }
      }
     },
     "localname": "DebtInstrumentPrincipalOutstanding",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_DeferredTaxAssetsLeaseObligation": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 5.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Deferred tax assets lease obligation.",
        "label": "Deferred Tax Assets Lease Obligation",
        "terseLabel": "Lease obligation"
       }
      }
     },
     "localname": "DeferredTaxAssetsLeaseObligation",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_DeferredTaxExpenseBenefitAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Deferred tax expense benefit.",
        "label": "Deferred Tax Expense Benefit [Abstract]",
        "terseLabel": "Deferred"
       }
      }
     },
     "localname": "DeferredTaxExpenseBenefitAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_DeferredTaxLiabilitiesDiscountOnConvertibleNotes": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 4.0,
       "parentTag": "us-gaap_DeferredIncomeTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Deferred tax liabilities discount on convertible notes.",
        "label": "Deferred Tax Liabilities Discount On Convertible Notes",
        "terseLabel": "Convertible debt, net of issuance costs"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesDiscountOnConvertibleNotes",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_DeferredTaxLiabilitiesInvestmentInConsolidatedSubsidiary": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_DeferredIncomeTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Deferred tax liabilities investment in consolidated subsidiary.",
        "label": "Deferred Tax Liabilities Investment In Consolidated Subsidiary",
        "terseLabel": "Deferred tax on investment in subsidiary"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesInvestmentInConsolidatedSubsidiary",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_DeferredTaxLiabilitiesPrepaidExpenseBenefit": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_DeferredIncomeTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Deferred tax liabilities prepaid expenses benefit.",
        "label": "Deferred Tax Liabilities Prepaid Expense Benefit",
        "terseLabel": "Prepaid royalties"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesPrepaidExpenseBenefit",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_DeferredTaxLiabilitiesPropertyPlantAndEquipmentAndIntangibles": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_DeferredIncomeTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Deferred tax liabilities property plant and equipment and intangibles.",
        "label": "Deferred Tax Liabilities Property Plant And Equipment And Intangibles",
        "terseLabel": "Property and equipment and intangibles"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesPropertyPlantAndEquipmentAndIntangibles",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_DefinedBenefitPensionPlanAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Defined benefit pension plan.",
        "label": "Defined Benefit Pension Plan [Abstract]"
       }
      }
     },
     "localname": "DefinedBenefitPensionPlanAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "xbrltype": "stringItemType"
    },
    "altr_DefinedBenefitPensionPlanAssetsNoncurrent": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_DefinedBenefitPlanBenefitObligation",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of asset, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan.",
        "label": "Defined Benefit Pension Plan Assets Noncurrent",
        "terseLabel": "Other long-term assets"
       }
      }
     },
     "localname": "DefinedBenefitPensionPlanAssetsNoncurrent",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_DisclosureSupplementaryInformationAdditionalInformationDetailAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Disclosure Supplementary Information Additional Information Detail [Abstract]",
        "terseLabel": "Disclosure - Supplementary Information - Additional Information (Detail) [Abstract]"
       }
      }
     },
     "localname": "DisclosureSupplementaryInformationAdditionalInformationDetailAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "xbrltype": "stringItemType"
    },
    "altr_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetailAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Disclosure Supplementary Information Schedule Of Other Expense Income Net Detail [Abstract]",
        "terseLabel": "Disclosure - Supplementary Information - Schedule of Other Expense (Income), Net (Detail) [Abstract]"
       }
      }
     },
     "localname": "DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetailAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "xbrltype": "stringItemType"
    },
    "altr_DocumentAndEntityInformationLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Document and entity information.",
        "label": "Document And Entity Information [Line Items]",
        "terseLabel": "Document And Entity Information [Line Items]"
       }
      }
     },
     "localname": "DocumentAndEntityInformationLineItems",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_DocumentAndEntityInformationTable": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Document and entity information table.",
        "label": "Document And Entity Information [Table]",
        "terseLabel": "Document And Entity Information [Table]"
       }
      }
     },
     "localname": "DocumentAndEntityInformationTable",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_EBITDAToConsolidatedInterestExpenseRatio": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "EBITDA To Consolidated Interest Expense Ratio",
        "label": "E B I T D A To Consolidated Interest Expense Ratio",
        "terseLabel": "EBITDA to cash Consolidated Interest Expense ratio"
       }
      }
     },
     "localname": "EBITDAToConsolidatedInterestExpenseRatio",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "altr_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxWithholdingAmount": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 6.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Effective income tax rate reconciliation foreign income tax withholding amount.",
        "label": "Effective Income Tax Rate Reconciliation Foreign Income Tax Withholding Amount",
        "terseLabel": "Foreign withholding taxes"
       }
      }
     },
     "localname": "EffectiveIncomeTaxRateReconciliationForeignIncomeTaxWithholdingAmount",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_EffectiveIncomeTaxRateReconciliationRepurchaseOfConvertibleSeniorNotes": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 14.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to repurchase of convertible senior notes.",
        "label": "Effective Income Tax Rate Reconciliation, Repurchase of Convertible Senior Notes",
        "terseLabel": "Repurchase of convertible senior notes"
       }
      }
     },
     "localname": "EffectiveIncomeTaxRateReconciliationRepurchaseOfConvertibleSeniorNotes",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_EmployeeStockOptionAndEmployeeStockPurchasePlanMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Employee stock option and employee stock purchase plan [Member]",
        "label": "Employee Stock Option And Employee Stock Purchase Plan [Member]",
        "terseLabel": "Stock Options and ESPP [Member]"
       }
      }
     },
     "localname": "EmployeeStockOptionAndEmployeeStockPurchasePlanMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntiDilutiveSharesExcludedFromComputationOfDilutedNetLossPerShareDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_EurodollarLoansMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Eurodollar loans.",
        "label": "Eurodollar Loans [Member]",
        "terseLabel": "Eurodollar Loans [Member]"
       }
      }
     },
     "localname": "EurodollarLoansMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ExpenseOnRepurchaseOfConvertibleSeniorNote": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_NonoperatingIncomeExpense",
       "weight": -1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 6.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Expense on repurchase of convertible senior note.",
        "label": "Expense On Repurchase Of Convertible Senior Note",
        "terseLabel": "Expense on repurchase of convertible senior notes"
       }
      }
     },
     "localname": "ExpenseOnRepurchaseOfConvertibleSeniorNote",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_FairValueExpenseRecognized": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Fair value expense recognized.",
        "label": "Fair Value Expense Recognized",
        "terseLabel": "Fair value expense recognized"
       }
      }
     },
     "localname": "FairValueExpenseRecognized",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_FinanceLeaseCost": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Finance lease cost.",
        "label": "Finance Lease Cost",
        "totalLabel": "Total finance lease cost"
       }
      }
     },
     "localname": "FinanceLeaseCost",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_FinanceLeaseCostsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Finance lease costs [Abstract]",
        "label": "Finance Lease Costs [Abstract]",
        "terseLabel": "Finance lease cost:"
       }
      }
     },
     "localname": "FinanceLeaseCostsAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_FinanceLeaseRightOfUseAssetAccumulatedDepreciation": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_FinanceLeaseRightOfUseAsset",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Finance lease right-of-use asset accumulated depreciation.",
        "label": "Finance Lease Right Of Use Asset Accumulated Depreciation",
        "negatedLabel": "Accumulated depreciation"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAssetAccumulatedDepreciation",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_FinanceLeaseRightOfUseAssetGross": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_FinanceLeaseRightOfUseAsset",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Finance lease right-of-use asset gross.",
        "label": "Finance Lease Right Of Use Asset Gross",
        "terseLabel": "Property and equipment"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAssetGross",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_FinanceLeasesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Finance leases.",
        "label": "Finance Leases [Abstract]",
        "terseLabel": "Finance leases:"
       }
      }
     },
     "localname": "FinanceLeasesAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_GainOnMarkToMarketAdjustmentOfContingentConsideration": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 5.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Gain on mark to market adjustment of contingent consideration.",
        "label": "Gain On Mark To Market Adjustment Of Contingent Consideration",
        "negatedLabel": "Gain on mark-to-market adjustment of contingent consideration",
        "terseLabel": "Gain on mark-to-market adjustment of contingent consideration"
       }
      }
     },
     "localname": "GainOnMarkToMarketAdjustmentOfContingentConsideration",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_GoodwillEffectOfForeignCurrencyTranslationGainLossAndOther": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Goodwill effect of foreign currency translation gain (loss) and other.",
        "label": "Goodwill Effect Of Foreign Currency Translation Gain Loss And Other",
        "terseLabel": "Effects of foreign currency translation and other"
       }
      }
     },
     "localname": "GoodwillEffectOfForeignCurrencyTranslationGainLossAndOther",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsChangesInCarryingAmountOfGoodwillAttributableToSoftwareReportableSegmentDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_GrantFunding": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Grant funding.",
        "label": "Grant Funding",
        "terseLabel": "Govenment funds"
       }
      }
     },
     "localname": "GrantFunding",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_ImpairmentChargeRecognizedInAdjustmentForRoyaltyContracts": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Impairment charge recognized in adjustment for royalty contracts.",
        "label": "Impairment Charge Recognized In Adjustment For Royalty Contracts",
        "terseLabel": "Impairment charge recognized in adjustment for royalty contracts"
       }
      }
     },
     "localname": "ImpairmentChargeRecognizedInAdjustmentForRoyaltyContracts",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_IncentiveAndNonqualifiedStockBasedPlanMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Incentive and nonqualified stock-based plan.",
        "label": "Incentive And Nonqualified Stock Based Plan [Member]",
        "terseLabel": "ISO Plan [Member]"
       }
      }
     },
     "localname": "IncentiveAndNonqualifiedStockBasedPlanMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_IncomeTaxDisclosureLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Income Tax Disclosure [Line Items]",
        "label": "Income Tax Disclosure [Line Items]",
        "terseLabel": "Income Tax Disclosure [Line Items]"
       }
      }
     },
     "localname": "IncomeTaxDisclosureLineItems",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_IncomeTaxDisclosureTable": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Income Tax Disclosure [Table]",
        "label": "Income Tax Disclosure [Table]",
        "terseLabel": "Income Tax Disclosure [Table]"
       }
      }
     },
     "localname": "IncomeTaxDisclosureTable",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_IncomeTaxReconciliationEffectOfChangesInTaxLaws": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 3.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Income tax reconciliation effect of changes in tax laws.",
        "label": "Income Tax Reconciliation Effect Of Changes In Tax Laws",
        "terseLabel": "U.S. effect of changes in tax laws"
       }
      }
     },
     "localname": "IncomeTaxReconciliationEffectOfChangesInTaxLaws",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_IncreaseDecreaseInUnrestrictedDomesticCash": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Increase decrease in unrestricted domestic cash.",
        "label": "Increase Decrease In Unrestricted Domestic Cash",
        "terseLabel": "Increase in unrestricted domestic cash"
       }
      }
     },
     "localname": "IncreaseDecreaseInUnrestrictedDomesticCash",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_IncreaseInDeferredTaxAssetsInProcessResearchAndDevelopment": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Increase in Deferred Tax Assets in Process Research and Development",
        "label": "Increase in Deferred Tax Assets in Process Research and Development"
       }
      }
     },
     "localname": "IncreaseInDeferredTaxAssetsInProcessResearchAndDevelopment",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_InterestIncomeAndOther": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail": {
       "order": 5.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Interest income and other.",
        "label": "Interest Income And Other",
        "terseLabel": "Special adjustments, interest income and other"
       }
      }
     },
     "localname": "InterestIncomeAndOther",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_LesseeOperatingAndFinanceLeasesDisclosureTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Lessee operating and finance leases.",
        "label": "Lessee Operating And Finance Leases Disclosure [Text Block]",
        "terseLabel": "Leases"
       }
      }
     },
     "localname": "LesseeOperatingAndFinanceLeasesDisclosureTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeases"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_LesseeOperatingAndFinanceLeasesOptionsToTerminateLeasesTerm": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Lessee operating and finance leases options to terminate leases term.",
        "label": "Lessee Operating And Finance Leases Options To Terminate Leases Term",
        "terseLabel": "Leases, options to terminate leases"
       }
      }
     },
     "localname": "LesseeOperatingAndFinanceLeasesOptionsToTerminateLeasesTerm",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "altr_LesseeRemainingLeaseTerm": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Lessee remaining lease term.",
        "label": "Lessee Remaining Lease Term",
        "terseLabel": "Leases, remaining lease term"
       }
      }
     },
     "localname": "LesseeRemainingLeaseTerm",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "altr_LineOfCreditFacilityIncreaseInBorrowingCapacity": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line Of Credit Facility Increase In Borrowing Capacity",
        "label": "Line Of Credit Facility Increase In Borrowing Capacity",
        "terseLabel": "Increase in line of credit borrowing capacity"
       }
      }
     },
     "localname": "LineOfCreditFacilityIncreaseInBorrowingCapacity",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_LongLivedAssets": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Long lived assets.",
        "label": "Long Lived Assets"
       }
      }
     },
     "localname": "LongLivedAssets",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_MaintenanceAndOtherServicesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Maintenance and other services.",
        "label": "Maintenance And Other Services [Member]",
        "terseLabel": "Maintenance and Other Services [Member]"
       }
      }
     },
     "localname": "MaintenanceAndOtherServicesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_MarkToMarketAdjustmentOfContingentConsideration": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 13.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Mark-To-Market Adjustment of Contingent Consideration",
        "label": "Mark-To-Market Adjustment of Contingent Consideration",
        "negatedLabel": "Mark-to-market adjustment of contingent consideration",
        "terseLabel": "Mark-to-market adjustment of contingent consideration"
       }
      }
     },
     "localname": "MarkToMarketAdjustmentOfContingentConsideration",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_MatrixCapitalManagementCompanyLimitedPartnerMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Matrix capital management company limited partner.",
        "label": "Matrix Capital Management Company Limited Partner [Member]",
        "terseLabel": "Matrix Capital Management Company LP [Member]"
       }
      }
     },
     "localname": "MatrixCapitalManagementCompanyLimitedPartnerMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_MaximumLeverageRatio": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Maximum leverage ratio.",
        "label": "Maximum Leverage Ratio",
        "terseLabel": "Maximum leverage ratio"
       }
      }
     },
     "localname": "MaximumLeverageRatio",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "altr_MezzanineEquityPolicyTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Mezzanine equity policy.",
        "label": "Mezzanine Equity Policy [Text Block]",
        "terseLabel": "Mezzanine equity"
       }
      }
     },
     "localname": "MezzanineEquityPolicyTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_MonthlyParticipantContributionsLimitedToPreventPrejudicialAdvantagesToHigherCompensatedEmployees": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Monthly participant contributions limited to prevent prejudicial advantages to higher compensated employees.",
        "label": "Monthly Participant Contributions Limited To Prevent Prejudicial Advantages To Higher Compensated Employees",
        "terseLabel": "Monthly participant contributions limited to prevent prejudicial advantages to higher compensated employees"
       }
      }
     },
     "localname": "MonthlyParticipantContributionsLimitedToPreventPrejudicialAdvantagesToHigherCompensatedEmployees",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_NCJudgementMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "NC judgement.",
        "label": "N C Judgement [Member]",
        "terseLabel": "NC Judgement [Member]"
       }
      }
     },
     "localname": "NCJudgementMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_NetOperatingLossCarryForwardsExpirationDates": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Net operating loss carry forwards expiration dates.",
        "label": "Net Operating Loss Carry Forwards Expiration Dates",
        "terseLabel": "U.S. general business credits and loss carryforwards, expiration year"
       }
      }
     },
     "localname": "NetOperatingLossCarryForwardsExpirationDates",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_NonqualifiedStockOptionPlanMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Nonqualified stock option plan.",
        "label": "Nonqualified Stock Option Plan [Member]",
        "terseLabel": "NSO Plan [Member]"
       }
      }
     },
     "localname": "NonqualifiedStockOptionPlanMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_NumberOfCustomerAccountingForMoreThanTenPercentOfRevenues": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number Of Customer Accounting For More Than Ten Percent Of Revenues",
        "label": "Number Of Customer Accounting For More Than Ten Percent Of Revenues",
        "terseLabel": "Number of individual customer accounted for 10% or more of revenue"
       }
      }
     },
     "localname": "NumberOfCustomerAccountingForMoreThanTenPercentOfRevenues",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "altr_NumberOfEqualVestingInstallments": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of equal vesting installments.",
        "label": "Number Of Equal Vesting Installments",
        "terseLabel": "Number of vesting equal annual installments"
       }
      }
     },
     "localname": "NumberOfEqualVestingInstallments",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "altr_NumberOfPrivatelyHeldCompaniesAcquired": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of privately held companies acquired.",
        "label": "Number Of Privately Held Companies Acquired",
        "terseLabel": "Number of privately held acquired"
       }
      }
     },
     "localname": "NumberOfPrivatelyHeldCompaniesAcquired",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "altr_OfferingPeriodBeginningDate": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Offering period beginning date.",
        "label": "Offering Period Beginning Date",
        "terseLabel": "Initial offering period beginning date"
       }
      }
     },
     "localname": "OfferingPeriodBeginningDate",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "dateItemType"
    },
    "altr_OfferingPeriodExpirationDate": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Offering period expiration date.",
        "label": "Offering Period Expiration Date",
        "terseLabel": "Offering period expiration date"
       }
      }
     },
     "localname": "OfferingPeriodExpirationDate",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "dateItemType"
    },
    "altr_OfficeFurnitureAndEquipmentMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Office furniture and equipment.",
        "label": "Office Furniture And Equipment [Member]",
        "terseLabel": "Office Furniture and Equipment [Member]"
       }
      }
     },
     "localname": "OfficeFurnitureAndEquipmentMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_OperatingLeasesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Operating leases.",
        "label": "Operating Leases [Abstract]",
        "terseLabel": "Operating leases:"
       }
      }
     },
     "localname": "OperatingLeasesAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_OperatingLossAndTaxCreditCarryforwardLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Operating Loss and Tax Credit Carryforward [Line Items]",
        "label": "Operating Loss And Tax Credit Carryforward [Line Items]",
        "terseLabel": "Operating Loss and Tax Credit Carryforward [Line Items]"
       }
      }
     },
     "localname": "OperatingLossAndTaxCreditCarryforwardLineItems",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_OperatingLossAndTaxCreditCarryforwardTable": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Operating Loss and Tax Credit Carryforward [Table]",
        "label": "Operating Loss And Tax Credit Carryforward [Table]",
        "terseLabel": "Operating Loss and Tax Credit Carryforward [Line Items]"
       }
      }
     },
     "localname": "OperatingLossAndTaxCreditCarryforwardTable",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_OperatingLossAndTaxCreditCarryforwards": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Operating loss and tax credit carryforwards.",
        "label": "Operating Loss And Tax Credit Carryforwards",
        "terseLabel": "Total operating loss and tax credit carryforwards"
       }
      }
     },
     "localname": "OperatingLossAndTaxCreditCarryforwards",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_OperatingLossCarryforwardsExpirationDateOne": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Operating loss carryforwards expiration date one.",
        "label": "Operating Loss Carryforwards Expiration Date One",
        "terseLabel": "Foreign general business credits and loss carryforwards, expiration year"
       }
      }
     },
     "localname": "OperatingLossCarryforwardsExpirationDateOne",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_OptionToPurchaseAdditionalPrincipalAmountOfNotesToInitialPurchaser": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Option to purchase additional principal amount of notes to initial purchaser.",
        "label": "Option to Purchase Additional Principal Amount of Notes to Initial Purchaser",
        "terseLabel": "Additional principal amount of notes to initial purchaser's"
       }
      }
     },
     "localname": "OptionToPurchaseAdditionalPrincipalAmountOfNotesToInitialPurchaser",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_OptionToPurchaseAdditionalPrincipalAmountOfNotesToUnderwriters": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Option to purchase additional principal amount of notes to underwriters.",
        "label": "Option To Purchase Additional Principal Amount Of Notes To Underwriters",
        "terseLabel": "Additional principal amount of notes to underwriters"
       }
      }
     },
     "localname": "OptionToPurchaseAdditionalPrincipalAmountOfNotesToUnderwriters",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_OtherAmericanCountriesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Other American Countries.",
        "label": "Other American Countries [Member]",
        "terseLabel": "Other American Countries [Member]"
       }
      }
     },
     "localname": "OtherAmericanCountriesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_OtherAsiaPacificCountriesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Other Asia Pacific Countries.",
        "label": "Other Asia Pacific Countries [Member]",
        "terseLabel": "Other Asia Pacific Countries [Member]"
       }
      }
     },
     "localname": "OtherAsiaPacificCountriesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_OtherBusinessAcquisitionsMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Other business acquisitions member.",
        "label": "Other Business Acquisitions [Member]",
        "terseLabel": "Other Business Acquisitions [Member]"
       }
      }
     },
     "localname": "OtherBusinessAcquisitionsMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_OtherEuropeMiddleEastAndAfricaCountriesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Other Europe, Middle East and Africa Countries.",
        "label": "Other Europe Middle East And Africa Countries [Member]",
        "terseLabel": "Other Europe, Middle East and Africa Countries [Member]"
       }
      }
     },
     "localname": "OtherEuropeMiddleEastAndAfricaCountriesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_OtherProductAndServiceMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Other product and service.",
        "label": "Other Product And Service [Member]",
        "terseLabel": "Other [Member]"
       }
      }
     },
     "localname": "OtherProductAndServiceMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_OverdraftAndLineOfCreditMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Overdraft and line of credit.",
        "label": "Overdraft And Line Of Credit [Member]",
        "terseLabel": "Overdraft and Line of Credit [Member]"
       }
      }
     },
     "localname": "OverdraftAndLineOfCreditMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_PaymentForRepurchaseOfCommonStockShares": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Payment for repurchase of common stock shares.",
        "label": "Payment For Repurchase Of Common Stock Shares",
        "terseLabel": "Payments for repurchase of common stock, Shares",
        "verboseLabel": "Repurchase and retirement of common stock, Shares"
       }
      }
     },
     "localname": "PaymentForRepurchaseOfCommonStockShares",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "altr_PercentageOfNetRevenuesThroughIndirectChannels": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Percentage of net revenues through indirect channels.",
        "label": "Percentage Of Net Revenues Through Indirect Channels",
        "terseLabel": "Percentage of net revenues through indirect channels"
       }
      }
     },
     "localname": "PercentageOfNetRevenuesThroughIndirectChannels",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "altr_PerpetualLicensesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Perpetual licenses.",
        "label": "Perpetual Licenses [Member]",
        "terseLabel": "Perpetual Licenses [Member]"
       }
      }
     },
     "localname": "PerpetualLicensesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_PolliwagCorporationLimitedMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Polliwag corporation limited.",
        "label": "Polliwag Corporation Limited [Member]",
        "terseLabel": "Polliwog Co. Ltd. [Member]"
       }
      }
     },
     "localname": "PolliwagCorporationLimitedMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_PowersimIncMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Powersim Inc Member.",
        "label": "Powersim Inc [Member]",
        "terseLabel": "Powersim Inc [Member]"
       }
      }
     },
     "localname": "PowersimIncMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ProceedsFromEmployeeStockPurchasePlanContributions": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 3.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Proceeds from employee stock purchase plan contributions.",
        "label": "Proceeds From Employee Stock Purchase Plan Contributions",
        "terseLabel": "Proceeds from employee stock purchase plan contributions"
       }
      }
     },
     "localname": "ProceedsFromEmployeeStockPurchasePlanContributions",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_ProductOneMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Product 1 [Member]",
        "label": "Product One [Member]",
        "terseLabel": "Automotive Industry [Member]"
       }
      }
     },
     "localname": "ProductOneMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ProfessionalSoftwareServicesHardwareRevenueMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Professional software services, hardware revenue.",
        "label": "Professional Software Services Hardware Revenue [Member]",
        "terseLabel": "Professional Software Services, Hardware Revenue [Member]"
       }
      }
     },
     "localname": "ProfessionalSoftwareServicesHardwareRevenueMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ProfessionalSoftwareServicesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Professional software services.",
        "label": "Professional Software Services [Member]",
        "terseLabel": "Professional Software Services [Member]"
       }
      }
     },
     "localname": "ProfessionalSoftwareServicesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_PromissoryNotesIssuedAndDeferredPaymentObligationsForAcquisitions": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Promissory notes issued and deferred payment obligations for acquisitions.",
        "label": "Promissory Notes Issued And Deferred Payment Obligations For Acquisitions",
        "terseLabel": "Promissory notes issued and deferred payment obligations for acquisitions"
       }
      }
     },
     "localname": "PromissoryNotesIssuedAndDeferredPaymentObligationsForAcquisitions",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_PutRightExercisePeriod": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Put right exercise period.",
        "label": "Put Right Exercise Period",
        "terseLabel": "Put right exercise period from date of purchase"
       }
      }
     },
     "localname": "PutRightExercisePeriod",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "altr_RapidMinerMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Rapid miner member.",
        "label": "Rapid Miner [Member]",
        "terseLabel": "Rapid Miner [Member]"
       }
      }
     },
     "localname": "RapidMinerMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ReceivableForResearchAndDevelopmentTaxCreditPolicyTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Receivable for research and development tax credit.",
        "label": "Receivable For Research And Development Tax Credit Policy [Text Block]",
        "terseLabel": "Receivable for R&amp;D credit"
       }
      }
     },
     "localname": "ReceivableForResearchAndDevelopmentTaxCreditPolicyTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_RevenueFromContractsWithCustomersLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Revenue from contracts with customers.",
        "label": "Revenue From Contracts With Customers [Line Items]",
        "terseLabel": "Revenue From Contracts With Customers [Line Items]"
       }
      }
     },
     "localname": "RevenueFromContractsWithCustomersLineItems",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail1",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_RevenueFromContractsWithCustomersTable": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Revenue from contracts with customers.",
        "label": "Revenue From Contracts With Customers [Table]"
       }
      }
     },
     "localname": "RevenueFromContractsWithCustomersTable",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail1",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_RightOfUseAssetsObtainedInExchangeForLeaseObligationsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Right-of-use assets obtained in exchange for lease obligations.",
        "label": "Right Of Use Assets Obtained In Exchange For Lease Obligations [Abstract]",
        "terseLabel": "ROU assets obtained in exchange for lease obligations:"
       }
      }
     },
     "localname": "RightOfUseAssetsObtainedInExchangeForLeaseObligationsAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalCashFlowInformationRelatedToLeasesDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_RightOfUseAssetsUnderFinanceLeasesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Right-of-use assets under finance leases.",
        "label": "Right Of Use Assets Under Finance Leases [Member]",
        "terseLabel": "Right-of-Use Assets Under Finance Leases [Member]"
       }
      }
     },
     "localname": "RightOfUseAssetsUnderFinanceLeasesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_ScheduleOfAccountsReceivableNetTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule of accounts Receivable Net Table Text Block",
        "label": "Schedule Of Accounts Receivable Net Table [Text Block]",
        "terseLabel": "Schedule of Accounts Receivable Net"
       }
      }
     },
     "localname": "ScheduleOfAccountsReceivableNetTableTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_ScheduleOfOtherIntangibleAssetsTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule of Other Intangible Assets [Table Text Block]",
        "label": "Schedule Of Other Intangible Assets Table [Text Block]",
        "terseLabel": "Schedule of Other Intangible Assets"
       }
      }
     },
     "localname": "ScheduleOfOtherIntangibleAssetsTableTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_ScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule of supplemental balance sheet information related to lease liabilities.",
        "label": "Schedule Of Supplemental Balance Sheet Information Related To Lease Liabilities Table [Text Block]",
        "terseLabel": "Schedule of Supplemental Balance Sheet Information Related to Lease Liabilities"
       }
      }
     },
     "localname": "ScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesTableTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_ScheduleOfSupplementalCashFlowInformationRelatedToLeasesTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule of supplemental cash flow information related to leases.",
        "label": "Schedule Of Supplemental Cash Flow Information Related To Leases Table [Text Block]",
        "terseLabel": "Schedule of Supplemental Cash Flow Information Related to Leases"
       }
      }
     },
     "localname": "ScheduleOfSupplementalCashFlowInformationRelatedToLeasesTableTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_SecuredCreditAgreementMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Description should be secured credit agreement. And custom label should be credit agreement.",
        "label": "Secured Credit Agreement [Member]",
        "terseLabel": "Secured Credit Agreement [Member]"
       }
      }
     },
     "localname": "SecuredCreditAgreementMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_SeniorSecuredLeverageRatio": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Senior secured leverage ratio.",
        "label": "Senior Secured Leverage Ratio",
        "terseLabel": "Senior secured leverage ratio"
       }
      }
     },
     "localname": "SeniorSecuredLeverageRatio",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "altr_SettlementOfConvertibleSeniorNotes": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Settlement of convertible senior notes.",
        "label": "Settlement of Convertible Senior Notes",
        "terseLabel": "Settlement of convertible senior notes"
       }
      }
     },
     "localname": "SettlementOfConvertibleSeniorNotes",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAndExercisableIntrinsicValue": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Share based compensation arrangement by share based payment award options outstanding and exercisable intrinsic value.",
        "label": "Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding And Exercisable Intrinsic Value",
        "terseLabel": "Aggregate intrinsic value, Outstanding and exercisable"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAndExercisableIntrinsicValue",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAndExercisableNumber": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Share based compensation arrangement by share based payment award options outstanding and exercisable number.",
        "label": "Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding And Exercisable Number",
        "periodEndLabel": "Number of options, Outstanding and exercisable, Ending Balance"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAndExercisableNumber",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "altr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAndExercisableWeightedAverageExercisePrice": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Share based compensation arrangement by share based payment award options outstanding and exercisable weighted average exercise price.",
        "label": "Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding And Exercisable Weighted Average Exercise Price",
        "periodEndLabel": "Weighted average exercise price per share, Outstanding and exercisable, Ending Balance",
        "terseLabel": "Weighted average exercise price per share, Outstanding and exercisable, Ending Balance"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAndExercisableWeightedAverageExercisePrice",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "altr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAndExercisableWeightedAverageRemainingContractualTerm": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Share based compensation arrangement by share based payment award options outstanding and exercisable weighted average remaining contractual term.",
        "label": "Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding And Exercisable Weighted Average Remaining Contractual Term",
        "terseLabel": "Weighted average remaining contractual term (years), Outstanding and exercisable"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAndExercisableWeightedAverageRemainingContractualTerm",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "altr_SoftwareAndOtherMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Software and other.",
        "label": "Software And Other [Member]",
        "terseLabel": "Software and Other [Member]"
       }
      }
     },
     "localname": "SoftwareAndOtherMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_SoftwareRelatedServiceMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Software related service.",
        "label": "Software Related Service [Member]",
        "terseLabel": "Software Related Services [Member]"
       }
      }
     },
     "localname": "SoftwareRelatedServiceMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_SoftwareRelatedServicesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Software related services.",
        "label": "Software Related Services [Member]",
        "terseLabel": "Software Related Services [Member]"
       }
      }
     },
     "localname": "SoftwareRelatedServicesMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_SoftwareSegmentMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Software.",
        "label": "Software Segment [Member]",
        "terseLabel": "Software [Member]"
       }
      }
     },
     "localname": "SoftwareSegmentMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_StockIssuedDuringPeriodSharesPrivatePlacementNewIssues": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock issued during period shares private placement new issues.",
        "label": "Stock Issued During Period Shares Private Placement New Issues",
        "terseLabel": "Issuance of common stock in private placement, net of issuance costs (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesPrivatePlacementNewIssues",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "altr_StockIssuedDuringPeriodSharesStockOptionsExercisedOther": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock issued during period shares stock options exercised other.",
        "label": "Stock Issued During Period Shares Stock Options Exercised Other",
        "terseLabel": "Exercise of stock options and other (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesStockOptionsExercisedOther",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "altr_StockIssuedDuringPeriodValuePrivatePlacementNewIssues": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock issued during period value private placement new issues.",
        "label": "Stock Issued During Period Value Private Placement New Issues",
        "terseLabel": "Issuance of common stock in private placement, net of issuance costs"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValuePrivatePlacementNewIssues",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_StockIssuedDuringPeriodValueStockOptionsExercisedOther": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock issued during period value stock options exercised other.",
        "label": "Stock Issued During Period Value Stock Options Exercised Other",
        "terseLabel": "Exercise of stock options and other"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValueStockOptionsExercisedOther",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_StockPurchaseAgreementMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock purchase agreement.",
        "label": "Stock Purchase Agreement [Member]",
        "terseLabel": "Stock Purchase Agreement [Member]",
        "verboseLabel": "Stock Purchase Agreement [Member]"
       }
      }
     },
     "localname": "StockPurchaseAgreementMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_StockPurchaseProgramSharesAcquired": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock purchase program shares acquired.",
        "label": "Stock Purchase Program Shares Acquired",
        "terseLabel": "Number of shares repurchased"
       }
      }
     },
     "localname": "StockPurchaseProgramSharesAcquired",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "altr_StockRepurchaseProgramAveragePricePerShare": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock repurchase program average price per share.",
        "label": "Stock Repurchase Program Average Price Per Share",
        "terseLabel": "Stock repurchase program, Average price per share"
       }
      }
     },
     "localname": "StockRepurchaseProgramAveragePricePerShare",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "altr_StockRepurchaseProgramRepurchaseAmount": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock repurchase program repurchase amount",
        "label": "Stock Repurchase Program, Repurchase Amount",
        "terseLabel": "Stock repurchase program, Repurchase amount"
       }
      }
     },
     "localname": "StockRepurchaseProgramRepurchaseAmount",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "altr_SummaryOfOperatingLossAndTaxCreditCarryForwardsTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Summary of operating loss and tax credit carry forwards.",
        "label": "Summary Of Operating Loss And Tax Credit Carry Forwards Table [Text Block]",
        "terseLabel": "Summary of Operating Loss and Tax Credit Carryforwards"
       }
      }
     },
     "localname": "SummaryOfOperatingLossAndTaxCreditCarryForwardsTableTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_SummaryOfOtherIntangibleAssetsLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Summary of other intangible assets.",
        "label": "Summary Of Other Intangible Assets [Line Items]",
        "terseLabel": "Summary Of Other Intangible Assets [Line Items]"
       }
      }
     },
     "localname": "SummaryOfOtherIntangibleAssetsLineItems",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_SummaryOfOtherIntangibleAssetsTable": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Summary Of Other Intangible Assets [Table]",
        "label": "Summary Of Other Intangible Assets [Table]",
        "terseLabel": "Summary Of Other Intangible Assets [Table]"
       }
      }
     },
     "localname": "SummaryOfOtherIntangibleAssetsTable",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_SupplementaryInformationAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Supplementary information.",
        "label": "Supplementary Information [Abstract]",
        "terseLabel": "Property, Plant and Equipment [Abstract]"
       }
      }
     },
     "localname": "SupplementaryInformationAbstract",
     "nsuri": "http://www.altair.com/20221231",
     "xbrltype": "stringItemType"
    },
    "altr_SupplementaryInformationLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Supplementary information.",
        "label": "Supplementary Information [Line Items]",
        "terseLabel": "Supplementary Information [Line Items]"
       }
      }
     },
     "localname": "SupplementaryInformationLineItems",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_SupplementaryInformationTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Supplementary information.",
        "label": "Supplementary Information [Text Block]",
        "terseLabel": "Supplementary Information"
       }
      }
     },
     "localname": "SupplementaryInformationTextBlock",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureSupplementaryInformation1"
     ],
     "xbrltype": "textBlockItemType"
    },
    "altr_SwinglineLoansMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Swingline loans.",
        "label": "Swingline Loans [Member]",
        "terseLabel": "Swingline Loans [Member]"
       }
      }
     },
     "localname": "SwinglineLoansMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TaxCreditCarryForwardPeriod": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tax Credit Carry Forward Period",
        "label": "Tax Credit Carry Forward Period",
        "terseLabel": "Tax credit carryforward, period"
       }
      }
     },
     "localname": "TaxCreditCarryForwardPeriod",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "altr_TaxCreditCarryforwardExpirationDateOne": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tax credit carryforward expiration date one.",
        "label": "Tax Credit Carryforward Expiration Date One",
        "terseLabel": "U.S. foreign tax credits, expiration year"
       }
      }
     },
     "localname": "TaxCreditCarryforwardExpirationDateOne",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "altr_TaxCutsAndJobsActOf2017ForeignIncomeExemptionCriteriaSubjectToCorporateTaxRateMinimumPercentage": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tax cuts and jobs act of 2017, foreign income exemption criteria subject to corporate tax rate minimum percentage.",
        "label": "Tax Cuts And Jobs Act Of2017 Foreign Income Exemption Criteria Subject To Corporate Tax Rate Minimum Percentage",
        "terseLabel": "Tax cuts and jobs act, foreign income exemption criteria subject to corporate tax rate minimum percentage"
       }
      }
     },
     "localname": "TaxCutsAndJobsActOf2017ForeignIncomeExemptionCriteriaSubjectToCorporateTaxRateMinimumPercentage",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "altr_TaxDeductionMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tax deduction.",
        "label": "Tax Deduction [Member]",
        "terseLabel": "Tax Deduction [Member]"
       }
      }
     },
     "localname": "TaxDeductionMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TemporaryEquitySharesLapsed": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Temporary equity shares lapsed.",
        "label": "Temporary Equity Shares Lapsed",
        "terseLabel": "Mezzanine equity Lapsed"
       }
      }
     },
     "localname": "TemporaryEquitySharesLapsed",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "altr_TermBenchmarkLoansMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Term benchmark loans.",
        "label": "Term Benchmark Loans [Member]"
       }
      }
     },
     "localname": "TermBenchmarkLoansMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TermLicensesAndOtherHardwareRevenueMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Term licenses and other, hardware revenue.",
        "label": "Term Licenses And Other Hardware Revenue [Member]",
        "terseLabel": "Term Licenses and Other, Hardware Revenue [Member]"
       }
      }
     },
     "localname": "TermLicensesAndOtherHardwareRevenueMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TermLicensesAndOtherMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Term licenses and other.",
        "label": "Term Licenses And Other [Member]",
        "terseLabel": "Term Licenses and Other [Member]"
       }
      }
     },
     "localname": "TermLicensesAndOtherMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TheTimingOfPayrollDeductionsMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The timing of payroll deductions.",
        "label": "The Timing Of Payroll Deductions [Member]",
        "terseLabel": "The Timing of Payroll Deductions [Member]"
       }
      }
     },
     "localname": "TheTimingOfPayrollDeductionsMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TwentyNineteenCreditAgreementMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Twenty nineteen credit agreement.",
        "label": "Twenty Nineteen Credit Agreement [Member]",
        "terseLabel": "Twenty Nineteen Credit Agreement"
       }
      }
     },
     "localname": "TwentyNineteenCreditAgreementMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TwoThousandAndSeventeenEquityIncentivePlanMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Two thousand and seventeen equity incentive plan.",
        "label": "Two Thousand And Seventeen Equity Incentive Plan [Member]",
        "terseLabel": "2017 Plan [Member]"
       }
      }
     },
     "localname": "TwoThousandAndSeventeenEquityIncentivePlanMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TwoThousandAndTwelveIncentiveAndNonqualifiedStockOptionPlanMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Two thousand and twelve incentive and nonqualified stock option plan.",
        "label": "Two Thousand And Twelve Incentive And Nonqualified Stock Option Plan [Member]",
        "terseLabel": "2012 Plan [Member]"
       }
      }
     },
     "localname": "TwoThousandAndTwelveIncentiveAndNonqualifiedStockOptionPlanMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_TwoThousandAndTwentyOneEmployeeStockPurchasePlanMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Two thousand and twenty one employee stock purchase plan.",
        "label": "Two Thousand And Twenty One Employee Stock Purchase Plan [Member]",
        "terseLabel": "2021 Employee Stock Purchase Plan [Member]"
       }
      }
     },
     "localname": "TwoThousandAndTwentyOneEmployeeStockPurchasePlanMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_UnivaCorporationMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Univa Corporation.",
        "label": "Univa Corporation [Member]",
        "terseLabel": "Univa [Member]"
       }
      }
     },
     "localname": "UnivaCorporationMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_UnivaCorporationsMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Univa corporations.",
        "label": "Univa Corporations [Member]",
        "terseLabel": "Univa"
       }
      }
     },
     "localname": "UnivaCorporationsMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables"
     ],
     "xbrltype": "domainItemType"
    },
    "altr_WorldProgrammingMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "World Programming.",
        "label": "World Programming [Member]",
        "terseLabel": "World Programming [Member]"
       }
      }
     },
     "localname": "WorldProgrammingMember",
     "nsuri": "http://www.altair.com/20221231",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "country_DE": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "GERMANY",
        "terseLabel": "Germany [Member]"
       }
      }
     },
     "localname": "DE",
     "nsuri": "http://xbrl.sec.gov/country/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "country_FR": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "FRANCE",
        "terseLabel": "France [Member]"
       }
      }
     },
     "localname": "FR",
     "nsuri": "http://xbrl.sec.gov/country/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "country_JP": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "JAPAN",
        "terseLabel": "Japan [Member]"
       }
      }
     },
     "localname": "JP",
     "nsuri": "http://xbrl.sec.gov/country/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "country_US": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "UNITED STATES",
        "terseLabel": "United States [Member]"
       }
      }
     },
     "localname": "US",
     "nsuri": "http://xbrl.sec.gov/country/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "dei_AmendmentFlag": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.",
        "label": "Amendment Flag",
        "terseLabel": "Amendment Flag"
       }
      }
     },
     "localname": "AmendmentFlag",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_AuditorFirmId": {
     "auth_ref": [
      "r827",
      "r828",
      "r829"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "PCAOB issued Audit Firm Identifier",
        "label": "Auditor Firm ID",
        "terseLabel": "Auditor Firm ID"
       }
      }
     },
     "localname": "AuditorFirmId",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "nonemptySequenceNumberItemType"
    },
    "dei_AuditorLocation": {
     "auth_ref": [
      "r827",
      "r828",
      "r829"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Auditor Location",
        "terseLabel": "Auditor Location"
       }
      }
     },
     "localname": "AuditorLocation",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "internationalNameItemType"
    },
    "dei_AuditorName": {
     "auth_ref": [
      "r827",
      "r828",
      "r829"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Auditor Name",
        "terseLabel": "Auditor Name"
       }
      }
     },
     "localname": "AuditorName",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "internationalNameItemType"
    },
    "dei_CityAreaCode": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Area code of city",
        "label": "City Area Code",
        "terseLabel": "City Area Code"
       }
      }
     },
     "localname": "CityAreaCode",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_CoverAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Cover page.",
        "label": "Cover [Abstract]"
       }
      }
     },
     "localname": "CoverAbstract",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "xbrltype": "stringItemType"
    },
    "dei_CurrentFiscalYearEndDate": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "End date of current fiscal year in the format --MM-DD.",
        "label": "Current Fiscal Year End Date",
        "terseLabel": "Current Fiscal Year End Date"
       }
      }
     },
     "localname": "CurrentFiscalYearEndDate",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "gMonthDayItemType"
    },
    "dei_DocumentAnnualReport": {
     "auth_ref": [
      "r827",
      "r828",
      "r829"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Boolean flag that is true only for a form used as an annual report.",
        "label": "Document Annual Report",
        "terseLabel": "Document Annual Report"
       }
      }
     },
     "localname": "DocumentAnnualReport",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_DocumentFiscalPeriodFocus": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Fiscal period values are FY, Q1, Q2, and Q3.  1st, 2nd and 3rd quarter 10-Q or 10-QT statements have value Q1, Q2, and Q3 respectively, with 10-K, 10-KT or other fiscal year statements having FY.",
        "label": "Document Fiscal Period Focus",
        "terseLabel": "Document Fiscal Period Focus"
       }
      }
     },
     "localname": "DocumentFiscalPeriodFocus",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "fiscalPeriodItemType"
    },
    "dei_DocumentFiscalYearFocus": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "This is focus fiscal year of the document report in YYYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.",
        "label": "Document Fiscal Year Focus",
        "terseLabel": "Document Fiscal Year Focus"
       }
      }
     },
     "localname": "DocumentFiscalYearFocus",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "gYearItemType"
    },
    "dei_DocumentPeriodEndDate": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period.  The format of the date is YYYY-MM-DD.",
        "label": "Document Period End Date",
        "terseLabel": "Document Period End Date"
       }
      }
     },
     "localname": "DocumentPeriodEndDate",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "dateItemType"
    },
    "dei_DocumentTransitionReport": {
     "auth_ref": [
      "r830"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Boolean flag that is true only for a form used as a transition report.",
        "label": "Document Transition Report",
        "terseLabel": "Document Transition Report"
       }
      }
     },
     "localname": "DocumentTransitionReport",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_DocumentType": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.",
        "label": "Document Type",
        "terseLabel": "Document Type"
       }
      }
     },
     "localname": "DocumentType",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "submissionTypeItemType"
    },
    "dei_DocumentsIncorporatedByReferenceTextBlock": {
     "auth_ref": [
      "r825"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Documents incorporated by reference.",
        "label": "Documents Incorporated by Reference [Text Block]",
        "terseLabel": "Documents Incorporated by Reference"
       }
      }
     },
     "localname": "DocumentsIncorporatedByReferenceTextBlock",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "textBlockItemType"
    },
    "dei_EntityAddressAddressLine1": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Address Line 1 such as Attn, Building Name, Street Name",
        "label": "Entity Address, Address Line One",
        "terseLabel": "Entity Address, Address Line One"
       }
      }
     },
     "localname": "EntityAddressAddressLine1",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_EntityAddressCityOrTown": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Name of the City or Town",
        "label": "Entity Address, City or Town",
        "terseLabel": "Entity Address, City or Town"
       }
      }
     },
     "localname": "EntityAddressCityOrTown",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_EntityAddressPostalZipCode": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Code for the postal or zip code",
        "label": "Entity Address, Postal Zip Code",
        "terseLabel": "Entity Address, Postal Zip Code"
       }
      }
     },
     "localname": "EntityAddressPostalZipCode",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_EntityAddressStateOrProvince": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Name of the state or province.",
        "label": "Entity Address, State or Province",
        "terseLabel": "Entity Address, State or Province"
       }
      }
     },
     "localname": "EntityAddressStateOrProvince",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "stateOrProvinceItemType"
    },
    "dei_EntityCentralIndexKey": {
     "auth_ref": [
      "r824"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.",
        "label": "Entity Central Index Key",
        "terseLabel": "Entity Central Index Key"
       }
      }
     },
     "localname": "EntityCentralIndexKey",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "centralIndexKeyItemType"
    },
    "dei_EntityCommonStockSharesOutstanding": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument.",
        "label": "Entity Common Stock, Shares Outstanding",
        "terseLabel": "Entity Common Stock, Shares Outstanding"
       }
      }
     },
     "localname": "EntityCommonStockSharesOutstanding",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "sharesItemType"
    },
    "dei_EntityCurrentReportingStatus": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicate 'Yes' or 'No' whether registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. This information should be based on the registrant's current or most recent filing containing the related disclosure.",
        "label": "Entity Current Reporting Status",
        "terseLabel": "Entity Current Reporting Status"
       }
      }
     },
     "localname": "EntityCurrentReportingStatus",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "yesNoItemType"
    },
    "dei_EntityEmergingGrowthCompany": {
     "auth_ref": [
      "r824"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicate if registrant meets the emerging growth company criteria.",
        "label": "Entity Emerging Growth Company",
        "terseLabel": "Entity Emerging Growth Company"
       }
      }
     },
     "localname": "EntityEmergingGrowthCompany",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_EntityFileNumber": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.",
        "label": "Securities Act File Number",
        "terseLabel": "Entity File Number"
       }
      }
     },
     "localname": "EntityFileNumber",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "fileNumberItemType"
    },
    "dei_EntityFilerCategory": {
     "auth_ref": [
      "r824"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicate whether the registrant is one of the following: Large Accelerated Filer, Accelerated Filer, Non-accelerated Filer. Definitions of these categories are stated in Rule 12b-2 of the Exchange Act. This information should be based on the registrant's current or most recent filing containing the related disclosure.",
        "label": "Entity Filer Category",
        "terseLabel": "Entity Filer Category"
       }
      }
     },
     "localname": "EntityFilerCategory",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "filerCategoryItemType"
    },
    "dei_EntityIncorporationStateCountryCode": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Two-character EDGAR code representing the state or country of incorporation.",
        "label": "Entity Incorporation, State or Country Code",
        "terseLabel": "Entity Incorporation, State or Country Code"
       }
      }
     },
     "localname": "EntityIncorporationStateCountryCode",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "edgarStateCountryItemType"
    },
    "dei_EntityInteractiveDataCurrent": {
     "auth_ref": [
      "r831"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Boolean flag that is true when the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).",
        "label": "Entity Interactive Data Current",
        "terseLabel": "Entity Interactive Data Current"
       }
      }
     },
     "localname": "EntityInteractiveDataCurrent",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "yesNoItemType"
    },
    "dei_EntityPublicFloat": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The aggregate market value of the voting and non-voting common equity held by non-affiliates computed by reference to the price at which the common equity was last sold, or the average bid and asked price of such common equity, as of the last business day of the registrant's most recently completed second fiscal quarter.",
        "label": "Entity Public Float",
        "terseLabel": "Entity Public Float"
       }
      }
     },
     "localname": "EntityPublicFloat",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "monetaryItemType"
    },
    "dei_EntityRegistrantName": {
     "auth_ref": [
      "r824"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.",
        "label": "Entity Registrant Name",
        "verboseLabel": "Entity Registrant Name"
       }
      }
     },
     "localname": "EntityRegistrantName",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_EntityShellCompany": {
     "auth_ref": [
      "r824"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Boolean flag that is true when the registrant is a shell company as defined in Rule 12b-2 of the Exchange Act.",
        "label": "Entity Shell Company",
        "terseLabel": "Entity Shell Company"
       }
      }
     },
     "localname": "EntityShellCompany",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_EntitySmallBusiness": {
     "auth_ref": [
      "r824"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicates that the company is a Smaller Reporting Company (SRC).",
        "label": "Entity Small Business",
        "terseLabel": "Entity Small Business"
       }
      }
     },
     "localname": "EntitySmallBusiness",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_EntityTaxIdentificationNumber": {
     "auth_ref": [
      "r824"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.",
        "label": "Entity Tax Identification Number",
        "terseLabel": "Entity Tax Identification Number"
       }
      }
     },
     "localname": "EntityTaxIdentificationNumber",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "employerIdItemType"
    },
    "dei_EntityVoluntaryFilers": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicate 'Yes' or 'No' if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.",
        "label": "Entity Voluntary Filers",
        "terseLabel": "Entity Voluntary Filers"
       }
      }
     },
     "localname": "EntityVoluntaryFilers",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "yesNoItemType"
    },
    "dei_EntityWellKnownSeasonedIssuer": {
     "auth_ref": [
      "r832"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicate 'Yes' or 'No' if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Is used on Form Type: 10-K, 10-Q, 8-K, 20-F, 6-K, 10-K/A, 10-Q/A, 20-F/A, 6-K/A, N-CSR, N-Q, N-1A.",
        "label": "Entity Well-known Seasoned Issuer",
        "terseLabel": "Entity Well-known Seasoned Issuer"
       }
      }
     },
     "localname": "EntityWellKnownSeasonedIssuer",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "yesNoItemType"
    },
    "dei_IcfrAuditorAttestationFlag": {
     "auth_ref": [
      "r827",
      "r828",
      "r829"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "ICFR Auditor Attestation Flag",
        "terseLabel": "ICFR Auditor Attestation Flag"
       }
      }
     },
     "localname": "IcfrAuditorAttestationFlag",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_LocalPhoneNumber": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Local phone number for entity.",
        "label": "Local Phone Number",
        "terseLabel": "Local Phone Number"
       }
      }
     },
     "localname": "LocalPhoneNumber",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_Security12bTitle": {
     "auth_ref": [
      "r823"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Title of a 12(b) registered security.",
        "label": "Title of 12(b) Security",
        "terseLabel": "Title of 12(b) Security"
       }
      }
     },
     "localname": "Security12bTitle",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "securityTitleItemType"
    },
    "dei_SecurityExchangeName": {
     "auth_ref": [
      "r826"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Name of the Exchange on which a security is registered.",
        "label": "Security Exchange Name",
        "terseLabel": "Security Exchange Name"
       }
      }
     },
     "localname": "SecurityExchangeName",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "edgarExchangeCodeItemType"
    },
    "dei_TradingSymbol": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Trading symbol of an instrument as listed on an exchange.",
        "label": "Trading Symbol",
        "terseLabel": "Trading Symbol"
       }
      }
     },
     "localname": "TradingSymbol",
     "nsuri": "http://xbrl.sec.gov/dei/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "xbrltype": "tradingSymbolItemType"
    },
    "srt_AmericasMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Americas [Member]",
        "terseLabel": "Americas [Member]"
       }
      }
     },
     "localname": "AmericasMember",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_AsiaPacificMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Asia Pacific [Member]",
        "terseLabel": "Asia Pacific [Member]"
       }
      }
     },
     "localname": "AsiaPacificMember",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_ConsolidatedEntitiesAxis": {
     "auth_ref": [
      "r300",
      "r637",
      "r638",
      "r641",
      "r642",
      "r719",
      "r779",
      "r888",
      "r891",
      "r892"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Consolidated Entities [Axis]"
       }
      }
     },
     "localname": "ConsolidatedEntitiesAxis",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_ConsolidatedEntitiesDomain": {
     "auth_ref": [
      "r300",
      "r637",
      "r638",
      "r641",
      "r642",
      "r719",
      "r779",
      "r888",
      "r891",
      "r892"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Consolidated Entities [Domain]"
       }
      }
     },
     "localname": "ConsolidatedEntitiesDomain",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_ContractualObligationFiscalYearMaturityScheduleTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Contractual Obligation, Fiscal Year Maturity [Table Text Block]",
        "terseLabel": "Future Purchase Obligations"
       }
      }
     },
     "localname": "ContractualObligationFiscalYearMaturityScheduleTableTextBlock",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember": {
     "auth_ref": [
      "r252",
      "r311",
      "r319",
      "r326",
      "r401",
      "r581",
      "r582",
      "r583",
      "r613",
      "r614",
      "r648",
      "r651",
      "r653",
      "r654",
      "r716"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Cumulative Effect, Period of Adoption, Adjustment [Member]",
        "terseLabel": "Cumulative Effect, Period of Adoption, Adjustment [Member]"
       }
      }
     },
     "localname": "CumulativeEffectPeriodOfAdoptionAdjustmentMember",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_CumulativeEffectPeriodOfAdoptionAxis": {
     "auth_ref": [
      "r252",
      "r311",
      "r319",
      "r326",
      "r401",
      "r581",
      "r582",
      "r583",
      "r613",
      "r614",
      "r648",
      "r651",
      "r653",
      "r654",
      "r716"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Cumulative Effect, Period of Adoption [Axis]",
        "terseLabel": "Cumulative Effect, Period of Adoption"
       }
      }
     },
     "localname": "CumulativeEffectPeriodOfAdoptionAxis",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_CumulativeEffectPeriodOfAdoptionDomain": {
     "auth_ref": [
      "r252",
      "r311",
      "r319",
      "r326",
      "r401",
      "r581",
      "r582",
      "r583",
      "r613",
      "r614",
      "r648",
      "r651",
      "r653",
      "r654",
      "r716"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Cumulative Effect, Period of Adoption [Domain]",
        "terseLabel": "Cumulative Effect, Period of Adoption"
       }
      }
     },
     "localname": "CumulativeEffectPeriodOfAdoptionDomain",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_LitigationCaseAxis": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Litigation Case [Axis]",
        "terseLabel": "Litigation Case"
       }
      }
     },
     "localname": "LitigationCaseAxis",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_LitigationCaseTypeDomain": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Litigation Case [Domain]",
        "terseLabel": "Litigation Case"
       }
      }
     },
     "localname": "LitigationCaseTypeDomain",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_MaximumMember": {
     "auth_ref": [
      "r435",
      "r436",
      "r437",
      "r438",
      "r540",
      "r724",
      "r743",
      "r780",
      "r781",
      "r797",
      "r810",
      "r822",
      "r893",
      "r947",
      "r948",
      "r949",
      "r950",
      "r951",
      "r952"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Maximum [Member]",
        "terseLabel": "Maximum [Member]"
       }
      }
     },
     "localname": "MaximumMember",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_MinimumMember": {
     "auth_ref": [
      "r435",
      "r436",
      "r437",
      "r438",
      "r540",
      "r724",
      "r743",
      "r780",
      "r781",
      "r797",
      "r810",
      "r822",
      "r893",
      "r947",
      "r948",
      "r949",
      "r950",
      "r951",
      "r952"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Minimum [Member]",
        "terseLabel": "Minimum [Member]"
       }
      }
     },
     "localname": "MinimumMember",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_ProductOrServiceAxis": {
     "auth_ref": [
      "r381",
      "r726",
      "r798",
      "r820",
      "r885",
      "r886",
      "r896",
      "r955"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Product and Service [Axis]",
        "terseLabel": "Product and Service"
       }
      }
     },
     "localname": "ProductOrServiceAxis",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_ProductsAndServicesDomain": {
     "auth_ref": [
      "r381",
      "r726",
      "r798",
      "r820",
      "r885",
      "r886",
      "r896",
      "r955"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Product and Service [Domain]",
        "terseLabel": "Product and Service"
       }
      }
     },
     "localname": "ProductsAndServicesDomain",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_RangeAxis": {
     "auth_ref": [
      "r435",
      "r436",
      "r437",
      "r438",
      "r523",
      "r540",
      "r572",
      "r573",
      "r574",
      "r723",
      "r724",
      "r743",
      "r780",
      "r781",
      "r797",
      "r810",
      "r822",
      "r879",
      "r893",
      "r948",
      "r949",
      "r950",
      "r951",
      "r952"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Statistical Measurement [Axis]",
        "terseLabel": "Statistical Measurement"
       }
      }
     },
     "localname": "RangeAxis",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_RangeMember": {
     "auth_ref": [
      "r435",
      "r436",
      "r437",
      "r438",
      "r523",
      "r540",
      "r572",
      "r573",
      "r574",
      "r723",
      "r724",
      "r743",
      "r780",
      "r781",
      "r797",
      "r810",
      "r822",
      "r879",
      "r893",
      "r948",
      "r949",
      "r950",
      "r951",
      "r952"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Statistical Measurement [Domain]",
        "terseLabel": "Statistical Measurement"
       }
      }
     },
     "localname": "RangeMember",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_SegmentGeographicalDomain": {
     "auth_ref": [
      "r382",
      "r383",
      "r770",
      "r771",
      "r772",
      "r773",
      "r774",
      "r775",
      "r776",
      "r777",
      "r778",
      "r799",
      "r821",
      "r896"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Geographical [Domain]",
        "terseLabel": "Geographical"
       }
      }
     },
     "localname": "SegmentGeographicalDomain",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_StatementGeographicalAxis": {
     "auth_ref": [
      "r382",
      "r383",
      "r763",
      "r770",
      "r771",
      "r772",
      "r773",
      "r774",
      "r775",
      "r776",
      "r777",
      "r778",
      "r799",
      "r821",
      "r896"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Geographical [Axis]",
        "terseLabel": "Geographical"
       }
      }
     },
     "localname": "StatementGeographicalAxis",
     "nsuri": "http://fasb.org/srt/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccountingPoliciesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Accounting Policies [Abstract]"
       }
      }
     },
     "localname": "AccountingPoliciesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccountingStandardsUpdate201912Member": {
     "auth_ref": [
      "r611",
      "r612",
      "r613",
      "r614"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accounting Standards Update 2019-12 Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes.",
        "label": "Accounting Standards Update 2019-12 [Member]",
        "terseLabel": "ASU 2019-12"
       }
      }
     },
     "localname": "AccountingStandardsUpdate201912Member",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AccountingStandardsUpdate202006Member": {
     "auth_ref": [
      "r645",
      "r646",
      "r647",
      "r648",
      "r649",
      "r650",
      "r651",
      "r652",
      "r653",
      "r654",
      "r655"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accounting Standards Update 2020-06 Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity.",
        "label": "Accounting Standards Update 2020-06 [Member]",
        "terseLabel": "ASU 2020-06 [Member]"
       }
      }
     },
     "localname": "AccountingStandardsUpdate202006Member",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AccountingStandardsUpdate202108Member": {
     "auth_ref": [
      "r631",
      "r632"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accounting Standards Update 2021-08 Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers.",
        "label": "Accounting Standards Update 2021-08 [Member]",
        "terseLabel": "ASU 2021-08"
       }
      }
     },
     "localname": "AccountingStandardsUpdate202108Member",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AccountingStandardsUpdateExtensibleList": {
     "auth_ref": [
      "r250",
      "r251",
      "r252",
      "r253",
      "r254",
      "r313",
      "r314",
      "r315",
      "r390",
      "r391",
      "r398",
      "r399",
      "r400",
      "r401",
      "r403",
      "r404",
      "r581",
      "r582",
      "r583",
      "r613",
      "r614",
      "r631",
      "r632",
      "r633",
      "r645",
      "r646",
      "r647",
      "r648",
      "r649",
      "r650",
      "r651",
      "r652",
      "r653",
      "r654",
      "r655",
      "r656",
      "r660",
      "r661",
      "r663",
      "r664",
      "r665",
      "r666",
      "r667",
      "r668",
      "r687",
      "r688",
      "r693",
      "r694",
      "r695",
      "r713",
      "r714",
      "r715",
      "r716",
      "r717",
      "r718",
      "r744",
      "r745",
      "r746",
      "r747",
      "r748",
      "r749",
      "r750",
      "r751",
      "r752",
      "r753",
      "r754",
      "r755",
      "r858"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicates amendment to accounting standards.",
        "label": "Accounting Standards Update [Extensible Enumeration]",
        "terseLabel": "Accounting Standards Update [Extensible Enumeration]"
       }
      }
     },
     "localname": "AccountingStandardsUpdateExtensibleList",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail"
     ],
     "xbrltype": "enumerationSetItemType"
    },
    "us-gaap_AccountsNotesAndLoansReceivableLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Accounts, Notes, Loans and Financing Receivable [Line Items]",
        "terseLabel": "Accounts Notes And Loans Receivable [Line Items]"
       }
      }
     },
     "localname": "AccountsNotesAndLoansReceivableLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccountsNotesLoansAndFinancingReceivableGrossAllowanceAndNetAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]"
       }
      }
     },
     "localname": "AccountsNotesLoansAndFinancingReceivableGrossAllowanceAndNetAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccountsPayableCurrent": {
     "auth_ref": [
      "r15",
      "r819"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 1.0,
       "parentTag": "us-gaap_LiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).",
        "label": "Accounts Payable, Current",
        "terseLabel": "Accounts payable",
        "totalLabel": "Accounts Payable, Current, Total"
       }
      }
     },
     "localname": "AccountsPayableCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock": {
     "auth_ref": [
      "r865"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of allowance for credit loss on accounts receivable.",
        "label": "Accounts Receivable, Allowance for Credit Loss [Table Text Block]",
        "terseLabel": "Schedule of Accounts Receivable Net"
       }
      }
     },
     "localname": "AccountsReceivableAllowanceForCreditLossTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_AccountsReceivableNetCurrent": {
     "auth_ref": [
      "r387",
      "r388"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfAccountsReceivableNetDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 1.0,
       "parentTag": "us-gaap_AssetsCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.",
        "label": "Accounts Receivable, after Allowance for Credit Loss, Current",
        "terseLabel": "Accounts receivable, net",
        "totalLabel": "Accounts receivable, net"
       }
      }
     },
     "localname": "AccountsReceivableNetCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfAccountsReceivableNetDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccrualForTaxesOtherThanIncomeTaxesCurrent": {
     "auth_ref": [
      "r19",
      "r157",
      "r784"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 7.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).",
        "label": "Accrual for Taxes Other than Income Taxes, Current",
        "terseLabel": "Non-income tax liabilities"
       }
      }
     },
     "localname": "AccrualForTaxesOtherThanIncomeTaxesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccruedIncomeTaxesCurrent": {
     "auth_ref": [
      "r2",
      "r218",
      "r238"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 3.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.",
        "label": "Accrued Income Taxes, Current",
        "terseLabel": "Income taxes payable"
       }
      }
     },
     "localname": "AccruedIncomeTaxesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccruedProfessionalFeesCurrent": {
     "auth_ref": [
      "r19"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 5.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).",
        "label": "Accrued Professional Fees, Current",
        "terseLabel": "Accrued professional fees"
       }
      }
     },
     "localname": "AccruedProfessionalFeesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccruedRoyaltiesCurrent": {
     "auth_ref": [
      "r19",
      "r784"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 6.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).",
        "label": "Accrued Royalties, Current",
        "terseLabel": "Accrued royalties"
       }
      }
     },
     "localname": "AccruedRoyaltiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember": {
     "auth_ref": [
      "r31",
      "r37",
      "r192",
      "r837",
      "r838",
      "r839"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accumulated other comprehensive (income) loss related to defined benefit plans attributable to the parent.",
        "label": "Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]",
        "terseLabel": "Retirement Related Benefit Plans [Member]"
       }
      }
     },
     "localname": "AccumulatedDefinedBenefitPlansAdjustmentMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment": {
     "auth_ref": [
      "r111",
      "r261"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_PropertyPlantAndEquipmentNet",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.",
        "label": "Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment",
        "periodEndLabel": "Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance",
        "periodStartLabel": "Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Beginning Balance",
        "terseLabel": "Less: accumulated depreciation and amortization",
        "totalLabel": "Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Total"
       }
      }
     },
     "localname": "AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Accumulated Other Comprehensive Income (Loss) [Line Items]",
        "terseLabel": "Accumulated Other Comprehensive Income (Loss) [Line Items]"
       }
      }
     },
     "localname": "AccumulatedOtherComprehensiveIncomeLossLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax": {
     "auth_ref": [
      "r34",
      "r36",
      "r37",
      "r269",
      "r738",
      "r751",
      "r755"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 4.0,
       "parentTag": "us-gaap_StockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.",
        "label": "Accumulated Other Comprehensive Income (Loss), Net of Tax",
        "terseLabel": "Accumulated other comprehensive loss",
        "totalLabel": "Accumulated Other Comprehensive Income (Loss), Net of Tax, Total"
       }
      }
     },
     "localname": "AccumulatedOtherComprehensiveIncomeLossNetOfTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]"
       }
      }
     },
     "localname": "AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccumulatedOtherComprehensiveIncomeLossTable": {
     "auth_ref": [
      "r279",
      "r280",
      "r675",
      "r676",
      "r677",
      "r678",
      "r679",
      "r682"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of information about components of accumulated other comprehensive income (loss).",
        "label": "Accumulated Other Comprehensive Income (Loss) [Table]",
        "terseLabel": "Accumulated Other Comprehensive Income Loss [Table]"
       }
      }
     },
     "localname": "AccumulatedOtherComprehensiveIncomeLossTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccumulatedOtherComprehensiveIncomeMember": {
     "auth_ref": [
      "r33",
      "r37",
      "r192",
      "r718",
      "r746",
      "r747",
      "r837",
      "r838",
      "r839",
      "r855",
      "r856",
      "r857"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accumulated increase (decrease) in equity from transactions and other events and circumstances from non-owner sources, attributable to the parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners.",
        "label": "AOCI Attributable to Parent [Member]",
        "terseLabel": "Accumulated Other Comprehensive Loss [Member]"
       }
      }
     },
     "localname": "AccumulatedOtherComprehensiveIncomeMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AccumulatedTranslationAdjustmentMember": {
     "auth_ref": [
      "r30",
      "r37",
      "r192",
      "r280",
      "r281",
      "r676",
      "r677",
      "r678",
      "r679",
      "r682",
      "r837"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accumulated other comprehensive income (loss) resulting from foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to the parent.",
        "label": "Accumulated Foreign Currency Adjustment Attributable to Parent [Member]",
        "terseLabel": "Foreign Currency Translation [Member]"
       }
      }
     },
     "localname": "AccumulatedTranslationAdjustmentMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife": {
     "auth_ref": [
      "r95"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.",
        "label": "Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life",
        "terseLabel": "Weighted-average useful life of acquired finite-lived intangible assets"
       }
      }
     },
     "localname": "AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_AdditionalPaidInCapitalCommonStock": {
     "auth_ref": [
      "r10"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_StockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Value received from shareholders in common stock-related transactions that are in excess of par value or stated value and amounts received from other stock-related transactions. Includes only common stock transactions (excludes preferred stock transactions). May be called contributed capital, capital in excess of par, capital surplus, or paid-in capital.",
        "label": "Additional Paid in Capital, Common Stock",
        "terseLabel": "Additional paid-in capital"
       }
      }
     },
     "localname": "AdditionalPaidInCapitalCommonStock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AdditionalPaidInCapitalMember": {
     "auth_ref": [
      "r581",
      "r582",
      "r583",
      "r855",
      "r856",
      "r857",
      "r936"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders.",
        "label": "Additional Paid-in Capital [Member]",
        "terseLabel": "Additional Paid-in Capital [Member]"
       }
      }
     },
     "localname": "AdditionalPaidInCapitalMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AdjustmentsForNewAccountingPronouncementsAxis": {
     "auth_ref": [
      "r250",
      "r251",
      "r252",
      "r253",
      "r254",
      "r313",
      "r314",
      "r315",
      "r316",
      "r326",
      "r390",
      "r391",
      "r398",
      "r399",
      "r400",
      "r401",
      "r403",
      "r404",
      "r581",
      "r582",
      "r583",
      "r611",
      "r612",
      "r613",
      "r614",
      "r631",
      "r632",
      "r633",
      "r645",
      "r646",
      "r647",
      "r648",
      "r649",
      "r650",
      "r651",
      "r652",
      "r653",
      "r654",
      "r655",
      "r656",
      "r660",
      "r661",
      "r663",
      "r664",
      "r665",
      "r666",
      "r667",
      "r668",
      "r687",
      "r688",
      "r693",
      "r694",
      "r695",
      "r696",
      "r713",
      "r714",
      "r715",
      "r716",
      "r717",
      "r718",
      "r728",
      "r729",
      "r730",
      "r744",
      "r745",
      "r746",
      "r747",
      "r748",
      "r749",
      "r750",
      "r751",
      "r752",
      "r753",
      "r754",
      "r755"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by amendment to accounting standards.",
        "label": "Accounting Standards Update [Axis]",
        "terseLabel": "Accounting Standards Update"
       }
      }
     },
     "localname": "AdjustmentsForNewAccountingPronouncementsAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue": {
     "auth_ref": [
      "r155",
      "r156",
      "r543"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase to additional paid-in capital (APIC) for recognition of cost for award under share-based payment arrangement.",
        "label": "APIC, Share-Based Payment Arrangement, Increase for Cost Recognition",
        "terseLabel": "Stock-based compensation",
        "totalLabel": "APIC, Share-Based Payment Arrangement, Increase for Cost Recognition, Total"
       }
      }
     },
     "localname": "AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]",
        "terseLabel": "Adjustments to reconcile net loss to net cash provided by operating activities:"
       }
      }
     },
     "localname": "AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AdvertisingCostsPolicyTextBlock": {
     "auth_ref": [
      "r586"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for advertising cost.",
        "label": "Advertising Cost [Policy Text Block]",
        "terseLabel": "Advertising costs"
       }
      }
     },
     "localname": "AdvertisingCostsPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_AdvertisingExpense": {
     "auth_ref": [
      "r587"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.",
        "label": "Advertising Expense",
        "terseLabel": "Advertising expenses"
       }
      }
     },
     "localname": "AdvertisingExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AllOtherSegmentsMember": {
     "auth_ref": [
      "r353",
      "r369",
      "r370",
      "r371",
      "r372",
      "r373"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Operating segments classified as other. Excludes intersegment elimination and reconciling items.",
        "label": "Other Segments [Member]",
        "verboseLabel": "All Other [Member]"
       }
      }
     },
     "localname": "AllOtherSegmentsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AllocatedShareBasedCompensationExpense": {
     "auth_ref": [
      "r576"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.",
        "label": "Share-Based Payment Arrangement, Expense",
        "terseLabel": "Stock-based compensation expense"
       }
      }
     },
     "localname": "AllocatedShareBasedCompensationExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock": {
     "auth_ref": [
      "r89",
      "r865"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of allowance for credit loss on financing receivable.",
        "label": "Financing Receivable, Allowance for Credit Loss [Table Text Block]",
        "terseLabel": "Schedule of Provision for Credit Loss"
       }
      }
     },
     "localname": "AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent": {
     "auth_ref": [
      "r270",
      "r389",
      "r405"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of allowance for credit loss on accounts receivable, classified as current.",
        "label": "Accounts Receivable, Allowance for Credit Loss, Current",
        "negatedPeriodEndLabel": "Balance, end of year",
        "negatedPeriodStartLabel": "Balance, beginning of year",
        "terseLabel": "Provision for credit loss"
       }
      }
     },
     "localname": "AllowanceForDoubtfulAccountsReceivableCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AmortizationOfFinancingCostsAndDiscounts": {
     "auth_ref": [
      "r470",
      "r690",
      "r795",
      "r796",
      "r845"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_InterestExpenseDebt",
       "weight": 1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 2.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.",
        "label": "Amortization of Debt Issuance Costs and Discounts",
        "terseLabel": "Amortization of debt discount and issuance costs",
        "totalLabel": "Amortization of Debt Issuance Costs and Discounts, Total",
        "verboseLabel": "Amortization of debt issuance cost and discount"
       }
      }
     },
     "localname": "AmortizationOfFinancingCostsAndDiscounts",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AmortizationOfIntangibleAssets": {
     "auth_ref": [
      "r65",
      "r93",
      "r100"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 3.0,
       "parentTag": "us-gaap_OperatingExpenses",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.",
        "label": "Amortization of Intangible Assets",
        "terseLabel": "Amortization of intangible assets"
       }
      }
     },
     "localname": "AmortizationOfIntangibleAssets",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount": {
     "auth_ref": [
      "r339"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.",
        "label": "Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount",
        "terseLabel": "Total shares excluded from calculation"
       }
      }
     },
     "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntiDilutiveSharesExcludedFromComputationOfDilutedNetLossPerShareDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis": {
     "auth_ref": [
      "r75"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of antidilutive security.",
        "label": "Antidilutive Securities [Axis]",
        "terseLabel": "Antidilutive Securities"
       }
      }
     },
     "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntiDilutiveSharesExcludedFromComputationOfDilutedNetLossPerShareDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]",
        "terseLabel": "Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]"
       }
      }
     },
     "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntiDilutiveSharesExcludedFromComputationOfDilutedNetLossPerShareDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AntidilutiveSecuritiesNameDomain": {
     "auth_ref": [
      "r75"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Incremental common shares attributable to securities that were not included in diluted earnings per share (EPS) because to do so would increase EPS amounts or decrease loss per share amounts for the period presented.",
        "label": "Antidilutive Securities, Name [Domain]",
        "terseLabel": "Antidilutive Securities, Name"
       }
      }
     },
     "localname": "AntidilutiveSecuritiesNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntiDilutiveSharesExcludedFromComputationOfDilutedNetLossPerShareDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ArrangementsAndNonarrangementTransactionsMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Collaborative arrangement and arrangement other than collaborative applicable to revenue-generating activity or operations.",
        "label": "Collaborative Arrangement and Arrangement Other than Collaborative [Domain]",
        "terseLabel": "Collaborative Arrangement and Arrangement Other than Collaborative"
       }
      }
     },
     "localname": "ArrangementsAndNonarrangementTransactionsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AssetImpairmentCharges": {
     "auth_ref": [
      "r65",
      "r108"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.",
        "label": "Asset Impairment Charges",
        "terseLabel": "Impairment losses",
        "totalLabel": "Asset Impairment Charges, Total"
       }
      }
     },
     "localname": "AssetImpairmentCharges",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_Assets": {
     "auth_ref": [
      "r216",
      "r237",
      "r265",
      "r296",
      "r365",
      "r371",
      "r377",
      "r394",
      "r439",
      "r440",
      "r441",
      "r442",
      "r443",
      "r444",
      "r445",
      "r446",
      "r447",
      "r637",
      "r641",
      "r659",
      "r819",
      "r889",
      "r890",
      "r945"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.",
        "label": "Assets",
        "totalLabel": "TOTAL ASSETS"
       }
      }
     },
     "localname": "Assets",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AssetsCurrent": {
     "auth_ref": [
      "r257",
      "r271",
      "r296",
      "r394",
      "r439",
      "r440",
      "r441",
      "r442",
      "r443",
      "r444",
      "r445",
      "r446",
      "r447",
      "r637",
      "r641",
      "r659",
      "r819",
      "r889",
      "r890",
      "r945"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 0.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.",
        "label": "Assets, Current",
        "totalLabel": "Total current assets"
       }
      }
     },
     "localname": "AssetsCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AssetsCurrentAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Assets, Current [Abstract]",
        "terseLabel": "CURRENT ASSETS"
       }
      }
     },
     "localname": "AssetsCurrentAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupCurrent": {
     "auth_ref": [
      "r106",
      "r819"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.",
        "label": "Assets Held-for-sale, Not Part of Disposal Group, Current",
        "terseLabel": "Assets held for sale - building and related assets",
        "totalLabel": "Assets Held-for-sale, Not Part of Disposal Group, Current, Total"
       }
      }
     },
     "localname": "AssetsHeldForSaleNotPartOfDisposalGroupCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AwardTypeAxis": {
     "auth_ref": [
      "r547",
      "r548",
      "r549",
      "r551",
      "r552",
      "r553",
      "r554",
      "r555",
      "r556",
      "r557",
      "r558",
      "r559",
      "r560",
      "r561",
      "r562",
      "r563",
      "r564",
      "r565",
      "r566",
      "r567",
      "r568",
      "r571",
      "r572",
      "r573",
      "r574",
      "r575"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of award under share-based payment arrangement.",
        "label": "Award Type [Axis]",
        "terseLabel": "Award Type"
       }
      }
     },
     "localname": "AwardTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_BalanceSheetLocationAxis": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by location on balance sheet (statement of financial position).",
        "label": "Balance Sheet Location [Axis]",
        "terseLabel": "Balance Sheet Location"
       }
      }
     },
     "localname": "BalanceSheetLocationAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_BalanceSheetLocationDomain": {
     "auth_ref": [
      "r193",
      "r196"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Location in the balance sheet (statement of financial position).",
        "label": "Balance Sheet Location [Domain]",
        "terseLabel": "Balance Sheet Location"
       }
      }
     },
     "localname": "BalanceSheetLocationDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_BuildingAndBuildingImprovementsMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Facility held for productive use including, but not limited to, office, production, storage and distribution facilities and any addition, improvement, or renovation to the structure, for example, but not limited to, interior masonry, interior flooring, electrical, and plumbing.",
        "label": "Building and Building Improvements [Member]",
        "terseLabel": "Building and Improvements [Member]"
       }
      }
     },
     "localname": "BuildingAndBuildingImprovementsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_BusinessAcquisitionAcquireeDomain": {
     "auth_ref": [
      "r629",
      "r808",
      "r809"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Identification of the acquiree in a material business combination (or series of individually immaterial business combinations), which may include the name or other type of identification of the acquiree.",
        "label": "Business Acquisition, Acquiree [Domain]",
        "terseLabel": "Business Acquisition, Acquiree"
       }
      }
     },
     "localname": "BusinessAcquisitionAcquireeDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_BusinessAcquisitionAxis": {
     "auth_ref": [
      "r174",
      "r175",
      "r629",
      "r808",
      "r809"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by business combination or series of individually immaterial business combinations.",
        "label": "Business Acquisition [Axis]",
        "terseLabel": "Business Acquisition"
       }
      }
     },
     "localname": "BusinessAcquisitionAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_BusinessAcquisitionEquityInterestIssuedOrIssuableDescription": {
     "auth_ref": [
      "r187"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Description of equity interests issued or issuable to acquire the entity.",
        "label": "Business Acquisition, Equity Interest Issued or Issuable, Description",
        "terseLabel": "Business acquisition, equity interest issued or issuable, description"
       }
      }
     },
     "localname": "BusinessAcquisitionEquityInterestIssuedOrIssuableDescription",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_BusinessAcquisitionEquityInterestIssuedOrIssuableValueAssigned": {
     "auth_ref": [
      "r187"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.",
        "label": "Business Acquisition, Equity Interest Issued or Issuable, Value Assigned",
        "terseLabel": "Business acquisition, shares issued value"
       }
      }
     },
     "localname": "BusinessAcquisitionEquityInterestIssuedOrIssuableValueAssigned",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued": {
     "auth_ref": [
      "r187"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of shares of equity interests issued or issuable to acquire entity.",
        "label": "Business Acquisition, Equity Interest Issued or Issuable, Number of Shares",
        "terseLabel": "Business acquisition, shares issued"
       }
      }
     },
     "localname": "BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_BusinessAcquisitionLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Business Acquisition [Line Items]",
        "terseLabel": "Business Acquisition [Line Items]"
       }
      }
     },
     "localname": "BusinessAcquisitionLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired": {
     "auth_ref": [
      "r173"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Percentage of voting equity interests acquired at the acquisition date in the business combination.",
        "label": "Business Acquisition, Percentage of Voting Interests Acquired",
        "terseLabel": "Business acquisition, percentage of interest acquired"
       }
      }
     },
     "localname": "BusinessAcquisitionPercentageOfVotingInterestsAcquired",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount": {
     "auth_ref": [
      "r188"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.",
        "label": "Business Acquisition, Goodwill, Expected Tax Deductible Amount",
        "terseLabel": "Goodwill deductible for tax purposes"
       }
      }
     },
     "localname": "BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationAcquisitionRelatedCosts": {
     "auth_ref": [
      "r172"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.",
        "label": "Business Combination, Acquisition Related Costs",
        "verboseLabel": "Acquisition related costs"
       }
      }
     },
     "localname": "BusinessCombinationAcquisitionRelatedCosts",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationAndAssetAcquisitionAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Business Combination and Asset Acquisition [Abstract]"
       }
      }
     },
     "localname": "BusinessCombinationAndAssetAcquisitionAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_BusinessCombinationConsiderationTransferred1": {
     "auth_ref": [
      "r183",
      "r184",
      "r186"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.",
        "label": "Business Combination, Consideration Transferred",
        "terseLabel": "Fair value of consideration transferred",
        "totalLabel": "Business Combination, Consideration Transferred, Total",
        "verboseLabel": "Fair value of consideration transferred"
       }
      }
     },
     "localname": "BusinessCombinationConsiderationTransferred1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable": {
     "auth_ref": [
      "r183",
      "r184"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.",
        "label": "Business Combination, Consideration Transferred, Equity Interests Issued and Issuable",
        "terseLabel": "Issuance of common stock in connection with acquisitions"
       }
      }
     },
     "localname": "BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationContingentConsiderationLiability": {
     "auth_ref": [
      "r182",
      "r185",
      "r635"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liability recognized arising from contingent consideration in a business combination.",
        "label": "Business Combination, Contingent Consideration, Liability",
        "totalLabel": "Business Combination, Contingent Consideration, Liability, Total",
        "verboseLabel": "Contingent consideration"
       }
      }
     },
     "localname": "BusinessCombinationContingentConsiderationLiability",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationDisclosureTextBlock": {
     "auth_ref": [
      "r189",
      "r630"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).",
        "label": "Business Combination Disclosure [Text Block]",
        "terseLabel": "Acquisitions"
       }
      }
     },
     "localname": "BusinessCombinationDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitions"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents": {
     "auth_ref": [
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents",
        "terseLabel": "Cash"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables": {
     "auth_ref": [
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables",
        "terseLabel": "Accounts receivable"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue": {
     "auth_ref": [
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 9.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred revenue expected to be recognized as such within one year or the normal operating cycle, if longer, assumed at the acquisition date.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue",
        "negatedLabel": "Deferred revenue"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther": {
     "auth_ref": [
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 8.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other",
        "negatedLabel": "Accounts payable and other liabilities"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities": {
     "auth_ref": [
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 10.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities",
        "negatedLabel": "Deferred tax liabilities and other tax reserves"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles": {
     "auth_ref": [
      "r176",
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 6.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of identifiable intangible assets recognized as of the acquisition date.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles",
        "terseLabel": "Finite-lived intangibles"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities": {
     "auth_ref": [
      "r177"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liabilities assumed at the acquisition date.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities",
        "terseLabel": "Net liabilities acquired",
        "totalLabel": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Total"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet": {
     "auth_ref": [
      "r176",
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net",
        "totalLabel": "Total net identifiable assets acquired and liabilities assumed"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]",
        "terseLabel": "Recognized amounts of identifiable assets acquired and liabilities assumed:"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets": {
     "auth_ref": [
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets",
        "terseLabel": "Other assets"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment": {
     "auth_ref": [
      "r176",
      "r177"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 4.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of property, plant, and equipment recognized as of the acquisition date.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment",
        "terseLabel": "Property and equipment",
        "totalLabel": "Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet": {
     "auth_ref": [
      "r177"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.",
        "label": "Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net",
        "terseLabel": "Remaining purchase price of",
        "totalLabel": "Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total"
       }
      }
     },
     "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_BusinessCombinationsPolicy": {
     "auth_ref": [
      "r171"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for completed business combinations (purchase method, acquisition method or combination of entities under common control). This accounting policy may include a general discussion of the purchase method or acquisition method of accounting (including for example, the treatment accorded contingent consideration, the identification of assets and liabilities, the purchase price allocation process, how the fair values of acquired assets and liabilities are determined) and the entity's specific application thereof. An entity that acquires another entity in a leveraged buyout transaction generally discloses the accounting policy followed by the acquiring entity in determining the basis used to value its interest in the acquired entity, and the rationale for that accounting policy.",
        "label": "Business Combinations Policy [Policy Text Block]",
        "terseLabel": "Business combinations"
       }
      }
     },
     "localname": "BusinessCombinationsPolicy",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_CapitalExpendituresIncurredButNotYetPaid": {
     "auth_ref": [
      "r69",
      "r70",
      "r71"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Future cash outflow to pay for purchases of fixed assets that have occurred.",
        "label": "Capital Expenditures Incurred but Not yet Paid",
        "terseLabel": "Property and equipment in accounts payable and other current liabilities"
       }
      }
     },
     "localname": "CapitalExpendituresIncurredButNotYetPaid",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CapitalizedContractCostAmortizationMethod": {
     "auth_ref": [
      "r407"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Description of method used for amortizing cost capitalized in obtaining or fulfilling contract with customer.",
        "label": "Capitalized Contract Cost, Amortization Method",
        "terseLabel": "Capitalized contract cost, amortization method"
       }
      }
     },
     "localname": "CapitalizedContractCostAmortizationMethod",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CapitalizedContractCostAmortizationPeriod": {
     "auth_ref": [
      "r866"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Capitalized Contract Cost, Amortization Period",
        "terseLabel": "Capitalized contract cost, amortization period"
       }
      }
     },
     "localname": "CapitalizedContractCostAmortizationPeriod",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_CapitalizedContractCostNetCurrent": {
     "auth_ref": [
      "r408"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as current.",
        "label": "Capitalized Contract Cost, Net, Current",
        "terseLabel": "Capitalized contract cost net, current"
       }
      }
     },
     "localname": "CapitalizedContractCostNetCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CapitalizedContractCostNetNoncurrent": {
     "auth_ref": [
      "r408"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent.",
        "label": "Capitalized Contract Cost, Net, Noncurrent",
        "terseLabel": "Capitalized contract cost net, noncurrent"
       }
      }
     },
     "localname": "CapitalizedContractCostNetNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CashAndCashEquivalentsAtCarryingValue": {
     "auth_ref": [
      "r67",
      "r259",
      "r783"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents",
       "weight": 1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 0.0,
       "parentTag": "us-gaap_AssetsCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.",
        "label": "Cash and Cash Equivalents, at Carrying Value",
        "terseLabel": "Cash and cash equivalents",
        "totalLabel": "Cash and Cash Equivalents, at Carrying Value, Total"
       }
      }
     },
     "localname": "CashAndCashEquivalentsAtCarryingValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents": {
     "auth_ref": [
      "r61",
      "r67",
      "r72"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.",
        "label": "Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents",
        "periodEndLabel": "Cash, cash equivalents and restricted cash at end of period",
        "periodStartLabel": "Cash, cash equivalents and restricted cash at beginning of year",
        "totalLabel": "Total cash, cash equivalents, and restricted cash"
       }
      }
     },
     "localname": "CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect": {
     "auth_ref": [
      "r61",
      "r209"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.",
        "label": "Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect",
        "totalLabel": "Net (decrease) increase in cash, cash equivalents and restricted cash"
       }
      }
     },
     "localname": "CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted": {
     "auth_ref": [
      "r250",
      "r251",
      "r312",
      "r390",
      "r391",
      "r395",
      "r396",
      "r397",
      "r398",
      "r399",
      "r611",
      "r631",
      "r632",
      "r643",
      "r645",
      "r646",
      "r656",
      "r660",
      "r662",
      "r663",
      "r664",
      "r667",
      "r668",
      "r687",
      "r692",
      "r693",
      "r694",
      "r695",
      "r713",
      "r714",
      "r728",
      "r729",
      "r744",
      "r745"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicates (true false) whether accounting standards update was adopted.",
        "label": "Change in Accounting Principle, Accounting Standards Update, Adopted [true false]",
        "terseLabel": "Change in Accounting Principle, Accounting Standards Update, Adopted [true false]"
       }
      }
     },
     "localname": "ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "booleanItemType"
    },
    "us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdoptionDate": {
     "auth_ref": [
      "r250",
      "r251",
      "r390",
      "r391",
      "r395",
      "r396",
      "r397",
      "r398",
      "r399",
      "r611",
      "r631",
      "r632",
      "r633",
      "r643",
      "r645",
      "r646",
      "r647",
      "r650",
      "r656",
      "r660",
      "r662",
      "r663",
      "r664",
      "r667",
      "r668",
      "r687",
      "r692",
      "r693",
      "r694",
      "r695",
      "r713",
      "r714",
      "r728",
      "r729",
      "r744",
      "r745",
      "r859"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Date accounting standards update was adopted, in YYYY-MM-DD format.",
        "label": "Change in Accounting Principle, Accounting Standards Update, Adoption Date",
        "terseLabel": "Change in Accounting Principle, Accounting Standards Update, Adoption Date"
       }
      }
     },
     "localname": "ChangeInAccountingPrincipleAccountingStandardsUpdateAdoptionDate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "dateItemType"
    },
    "us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateImmaterialEffect": {
     "auth_ref": [
      "r313",
      "r325",
      "r392",
      "r402",
      "r615"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicates (true false) whether effect from applying amendment to accounting standards is immaterial.",
        "label": "Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]",
        "terseLabel": "Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]"
       }
      }
     },
     "localname": "ChangeInAccountingPrincipleAccountingStandardsUpdateImmaterialEffect",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "booleanItemType"
    },
    "us-gaap_ClassOfStockDomain": {
     "auth_ref": [
      "r266",
      "r267",
      "r268",
      "r296",
      "r329",
      "r333",
      "r336",
      "r338",
      "r345",
      "r346",
      "r394",
      "r439",
      "r441",
      "r442",
      "r443",
      "r446",
      "r447",
      "r477",
      "r478",
      "r481",
      "r485",
      "r492",
      "r659",
      "r782",
      "r833",
      "r846",
      "r860"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Share of stock differentiated by the voting rights the holder receives. Examples include, but are not limited to, common stock, redeemable preferred stock, nonredeemable preferred stock, and convertible stock.",
        "label": "Class of Stock [Domain]",
        "terseLabel": "Class of Stock"
       }
      }
     },
     "localname": "ClassOfStockDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ClassOfStockLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Class of Stock [Line Items]",
        "terseLabel": "Class of Stock [Line Items]"
       }
      }
     },
     "localname": "ClassOfStockLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CommitmentsAndContingencies": {
     "auth_ref": [
      "r25",
      "r225",
      "r244"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 1.0,
       "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.",
        "label": "Commitments and Contingencies",
        "terseLabel": "Commitments and contingencies"
       }
      }
     },
     "localname": "CommitmentsAndContingencies",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CommitmentsAndContingenciesDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Commitments and Contingencies Disclosure [Abstract]"
       }
      }
     },
     "localname": "CommitmentsAndContingenciesDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_CommitmentsAndContingenciesDisclosureTextBlock": {
     "auth_ref": [
      "r117",
      "r432",
      "r433",
      "r766",
      "r887"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for commitments and contingencies.",
        "label": "Commitments and Contingencies Disclosure [Text Block]",
        "terseLabel": "Commitments and Contingencies"
       }
      }
     },
     "localname": "CommitmentsAndContingenciesDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingencies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_CommonClassAMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Classification of common stock representing ownership interest in a corporation.",
        "label": "Common Class A [Member]",
        "terseLabel": "Class A Common Stock [Member]"
       }
      }
     },
     "localname": "CommonClassAMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CommonClassBMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Classification of common stock that has different rights than Common Class A, representing ownership interest in a corporation.",
        "label": "Common Class B [Member]",
        "terseLabel": "Class B Common Stock [Member]"
       }
      }
     },
     "localname": "CommonClassBMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CommonStockCapitalSharesReservedForFutureIssuance": {
     "auth_ref": [
      "r26"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Aggregate number of common shares reserved for future issuance.",
        "label": "Common Stock, Capital Shares Reserved for Future Issuance",
        "terseLabel": "Common stock reserved for issuance"
       }
      }
     },
     "localname": "CommonStockCapitalSharesReservedForFutureIssuance",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_CommonStockDividendsPerShareDeclared": {
     "auth_ref": [
      "r140"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Aggregate dividends declared during the period for each share of common stock outstanding.",
        "label": "Common Stock, Dividends, Per Share, Declared",
        "terseLabel": "Common stock dividends"
       }
      }
     },
     "localname": "CommonStockDividendsPerShareDeclared",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_CommonStockMember": {
     "auth_ref": [
      "r855",
      "r856",
      "r936"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Stock that is subordinate to all other stock of the issuer.",
        "label": "Common Stock [Member]",
        "terseLabel": "Common Stock [Member]"
       }
      }
     },
     "localname": "CommonStockMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CommonStockParOrStatedValuePerShare": {
     "auth_ref": [
      "r9"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Face amount or stated value per share of common stock.",
        "label": "Common Stock, Par or Stated Value Per Share",
        "terseLabel": "Common stock, par value"
       }
      }
     },
     "localname": "CommonStockParOrStatedValuePerShare",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_CommonStockSharesAuthorized": {
     "auth_ref": [
      "r9"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The maximum number of common shares permitted to be issued by an entity's charter and bylaws.",
        "label": "Common Stock, Shares Authorized",
        "terseLabel": "Common stock, shares authorized"
       }
      }
     },
     "localname": "CommonStockSharesAuthorized",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_CommonStockSharesIssued": {
     "auth_ref": [
      "r9"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.",
        "label": "Common Stock, Shares, Issued",
        "terseLabel": "Common stock, shares issued"
       }
      }
     },
     "localname": "CommonStockSharesIssued",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_CommonStockSharesOutstanding": {
     "auth_ref": [
      "r9",
      "r133"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.",
        "label": "Common Stock, Shares, Outstanding",
        "periodEndLabel": "Common Stock, Shares, Outstanding, Ending Balance",
        "periodStartLabel": "Common Stock, Shares, Outstanding, Beginning Balance",
        "terseLabel": "Common stock, shares outstanding"
       }
      }
     },
     "localname": "CommonStockSharesOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_CommonStockValue": {
     "auth_ref": [
      "r9",
      "r819"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 1.0,
       "parentTag": "us-gaap_StockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.",
        "label": "Common Stock, Value, Issued",
        "terseLabel": "Common stock"
       }
      }
     },
     "localname": "CommonStockValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CompensationAndRetirementDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Retirement Benefits [Abstract]"
       }
      }
     },
     "localname": "CompensationAndRetirementDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_ComprehensiveIncomeNetOfTax": {
     "auth_ref": [
      "r38",
      "r275",
      "r277",
      "r284",
      "r734",
      "r740"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.",
        "label": "Comprehensive Income (Loss), Net of Tax, Attributable to Parent",
        "totalLabel": "Comprehensive loss"
       }
      }
     },
     "localname": "ComprehensiveIncomeNetOfTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ComprehensiveIncomeNoteTextBlock": {
     "auth_ref": [
      "r53",
      "r283",
      "r733",
      "r739"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income.",
        "label": "Comprehensive Income (Loss) Note [Text Block]",
        "terseLabel": "Accumulated Other Comprehensive Loss"
       }
      }
     },
     "localname": "ComprehensiveIncomeNoteTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLoss"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ConcentrationRiskBenchmarkDomain": {
     "auth_ref": [
      "r78",
      "r79",
      "r207",
      "r208",
      "r385",
      "r765"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The denominator in a calculation of a disclosed concentration risk percentage.",
        "label": "Concentration Risk Benchmark [Domain]",
        "terseLabel": "Concentration Risk Benchmark"
       }
      }
     },
     "localname": "ConcentrationRiskBenchmarkDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ConcentrationRiskByBenchmarkAxis": {
     "auth_ref": [
      "r78",
      "r79",
      "r207",
      "r208",
      "r385",
      "r756",
      "r765"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by benchmark of concentration risk.",
        "label": "Concentration Risk Benchmark [Axis]",
        "terseLabel": "Concentration Risk Benchmark"
       }
      }
     },
     "localname": "ConcentrationRiskByBenchmarkAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ConcentrationRiskByTypeAxis": {
     "auth_ref": [
      "r78",
      "r79",
      "r207",
      "r208",
      "r385",
      "r765",
      "r956"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of concentration risk, for example, but not limited to, asset, liability, net assets, geographic, customer, employees, supplier, lender.",
        "label": "Concentration Risk Type [Axis]",
        "terseLabel": "Concentration Risk Type"
       }
      }
     },
     "localname": "ConcentrationRiskByTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ConcentrationRiskPercentage1": {
     "auth_ref": [
      "r78",
      "r79",
      "r207",
      "r208",
      "r385"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the \"benchmark\" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.",
        "label": "Concentration Risk, Percentage",
        "terseLabel": "Concentration of credit risk, percentage"
       }
      }
     },
     "localname": "ConcentrationRiskPercentage1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ConcentrationRiskTypeDomain": {
     "auth_ref": [
      "r78",
      "r79",
      "r207",
      "r208",
      "r385",
      "r765"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "For an entity that discloses a concentration risk as a percentage of some financial balance or benchmark, identifies the type (for example, asset, liability, net assets, geographic, customer, employees, supplier, lender) of the concentration.",
        "label": "Concentration Risk Type [Domain]",
        "terseLabel": "Concentration Risk Type"
       }
      }
     },
     "localname": "ConcentrationRiskTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ConsolidationPolicyTextBlock": {
     "auth_ref": [
      "r191",
      "r786"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary.",
        "label": "Consolidation, Policy [Policy Text Block]",
        "terseLabel": "Principles of consolidation"
       }
      }
     },
     "localname": "ConsolidationPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ContractWithCustomerAssetNetCurrent": {
     "auth_ref": [
      "r494",
      "r496",
      "r517"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfAccountsReceivableNetDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_AccountsReceivableNetCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.",
        "label": "Contract with Customer, Asset, after Allowance for Credit Loss, Current",
        "terseLabel": "Contract assets",
        "totalLabel": "Contract with Customer, Asset, after Allowance for Credit Loss, Current, Total"
       }
      }
     },
     "localname": "ContractWithCustomerAssetNetCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfAccountsReceivableNetDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ContractWithCustomerLiabilityCurrent": {
     "auth_ref": [
      "r494",
      "r495",
      "r517"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 5.0,
       "parentTag": "us-gaap_LiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.",
        "label": "Contract with Customer, Liability, Current",
        "terseLabel": "Deferred revenue"
       }
      }
     },
     "localname": "ContractWithCustomerLiabilityCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ContractWithCustomerLiabilityNoncurrent": {
     "auth_ref": [
      "r494",
      "r495",
      "r517"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_Liabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.",
        "label": "Contract with Customer, Liability, Noncurrent",
        "terseLabel": "Deferred revenue, non-current"
       }
      }
     },
     "localname": "ContractWithCustomerLiabilityNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ContractWithCustomerLiabilityRevenueRecognized": {
     "auth_ref": [
      "r518"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.",
        "label": "Contract with Customer, Liability, Revenue Recognized",
        "terseLabel": "Deferred revenue, revenue recognized"
       }
      }
     },
     "localname": "ContractWithCustomerLiabilityRevenueRecognized",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ContractWithCustomerRefundLiabilityCurrent": {
     "auth_ref": [
      "r897"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 9.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer, classified as current.",
        "label": "Contract with Customer, Refund Liability, Current",
        "terseLabel": "Billings in excess of cost"
       }
      }
     },
     "localname": "ContractWithCustomerRefundLiabilityCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ConversionOfStockSharesConverted1": {
     "auth_ref": [
      "r69",
      "r70",
      "r71"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. \"Part noncash\" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.",
        "label": "Conversion of Stock, Shares Converted",
        "terseLabel": "Conversion from Class B to Class A common stock"
       }
      }
     },
     "localname": "ConversionOfStockSharesConverted1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ConvertibleDebtFairValueDisclosures": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.",
        "label": "Convertible Debt, Fair Value Disclosures",
        "terseLabel": "Fair value of convertible notes"
       }
      }
     },
     "localname": "ConvertibleDebtFairValueDisclosures",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ConvertibleDebtMember": {
     "auth_ref": [
      "r122",
      "r448",
      "r449",
      "r460",
      "r461",
      "r462",
      "r466",
      "r467",
      "r468",
      "r469",
      "r470",
      "r792",
      "r793",
      "r794",
      "r795",
      "r796"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.",
        "label": "Convertible Debt [Member]",
        "terseLabel": "Issuance of Convertible Debt [Member]"
       }
      }
     },
     "localname": "ConvertibleDebtMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ConvertibleDebtTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of convertible debt instrument. Includes, but is not limited to, principal amount and amortized premium or discount.",
        "label": "Convertible Debt [Table Text Block]",
        "terseLabel": "Schedule of Net Carrying Value of Liability Component of 2027 and 2024 Notes"
       }
      }
     },
     "localname": "ConvertibleDebtTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ConvertibleLongTermNotesPayable": {
     "auth_ref": [
      "r23"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 1.0,
       "parentTag": "us-gaap_Liabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.",
        "label": "Convertible Notes Payable, Noncurrent",
        "terseLabel": "Convertible senior notes, net",
        "totalLabel": "Net carrying amount"
       }
      }
     },
     "localname": "ConvertibleLongTermNotesPayable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ConvertibleNotesPayableCurrent": {
     "auth_ref": [
      "r19"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 6.0,
       "parentTag": "us-gaap_LiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying value as of the balance sheet date of the portion of long-term debt due within one year or the operating cycle if longer identified as Convertible Notes Payable. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.",
        "label": "Convertible Notes Payable, Current",
        "terseLabel": "Convertible senior notes, net",
        "totalLabel": "Net carrying amount"
       }
      }
     },
     "localname": "ConvertibleNotesPayableCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CostOfGoodsAndServicesSold": {
     "auth_ref": [
      "r46",
      "r726"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 1.0,
       "parentTag": "us-gaap_GrossProfit",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.",
        "label": "Cost of Goods and Services Sold",
        "terseLabel": "Total cost of revenue",
        "totalLabel": "Cost of Goods and Services Sold, Total"
       }
      }
     },
     "localname": "CostOfGoodsAndServicesSold",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CostOfSalesMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Primary financial statement caption encompassing cost of sales.",
        "label": "Cost of Sales [Member]",
        "terseLabel": "Cost of Revenue - Software [Member]"
       }
      }
     },
     "localname": "CostOfSalesMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CreditFacilityAxis": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of credit facility. Credit facilities provide capital to borrowers without the need to structure a loan for each borrowing.",
        "label": "Credit Facility [Axis]",
        "terseLabel": "Credit Facility"
       }
      }
     },
     "localname": "CreditFacilityAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CreditFacilityDomain": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Type of credit facility. Credit facilities provide capital to borrowers without the need to structure a loan for each borrowing.",
        "label": "Credit Facility [Domain]",
        "terseLabel": "Credit Facility"
       }
      }
     },
     "localname": "CreditFacilityDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CurrentFederalTaxExpenseBenefit": {
     "auth_ref": [
      "r849",
      "r929",
      "r931"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_CurrentIncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of current federal tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current national tax expense (benefit) for non-US (United States of America) jurisdiction.",
        "label": "Current Federal Tax Expense (Benefit)",
        "terseLabel": "U.S. Federal"
       }
      }
     },
     "localname": "CurrentFederalTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CurrentForeignTaxExpenseBenefit": {
     "auth_ref": [
      "r849",
      "r929"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_CurrentIncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.",
        "label": "Current Foreign Tax Expense (Benefit)",
        "terseLabel": "Non-U.S."
       }
      }
     },
     "localname": "CurrentForeignTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CurrentIncomeTaxExpenseBenefit": {
     "auth_ref": [
      "r170",
      "r608",
      "r619",
      "r849"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.",
        "label": "Current Income Tax Expense (Benefit)",
        "totalLabel": "Total current"
       }
      }
     },
     "localname": "CurrentIncomeTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CurrentStateAndLocalTaxExpenseBenefit": {
     "auth_ref": [
      "r849",
      "r929",
      "r931"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_CurrentIncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of current state and local tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current regional, territorial, and provincial tax expense (benefit) for non-US (United States of America) jurisdiction.",
        "label": "Current State and Local Tax Expense (Benefit)",
        "terseLabel": "U.S. State and Local"
       }
      }
     },
     "localname": "CurrentStateAndLocalTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CustomerRelationshipsMember": {
     "auth_ref": [
      "r180"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Customer relationship that exists between an entity and its customer, for example, but not limited to, tenant relationships.",
        "label": "Customer Relationships [Member]",
        "terseLabel": "Customer Relationships [Member]"
       }
      }
     },
     "localname": "CustomerRelationshipsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DebtConversionByUniqueDescriptionAxis": {
     "auth_ref": [
      "r69",
      "r71"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by description of debt issuances converted in a noncash or part noncash transaction.",
        "label": "Debt Conversion Description [Axis]",
        "terseLabel": "Debt Conversion Description"
       }
      }
     },
     "localname": "DebtConversionByUniqueDescriptionAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtConversionConvertedInstrumentSharesIssued1": {
     "auth_ref": [
      "r69",
      "r71"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. \"Part noncash\" refers to that portion of the transaction not resulting in cash receipts or payments in the period.",
        "label": "Debt Conversion, Converted Instrument, Shares Issued",
        "terseLabel": "Debt conversion, converted instrument, shares issued"
       }
      }
     },
     "localname": "DebtConversionConvertedInstrumentSharesIssued1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_DebtConversionNameDomain": {
     "auth_ref": [
      "r69",
      "r71"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The name of the original debt issue that has been converted in a noncash (or part noncash) transaction during the accounting period. \"Part noncash\" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.",
        "label": "Debt Conversion, Name [Domain]",
        "terseLabel": "Debt Conversion, Name"
       }
      }
     },
     "localname": "DebtConversionNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DebtDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Debt Disclosure [Abstract]"
       }
      }
     },
     "localname": "DebtDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtDisclosureTextBlock": {
     "auth_ref": [
      "r126",
      "r294",
      "r453",
      "r454",
      "r455",
      "r456",
      "r457",
      "r458",
      "r459",
      "r464",
      "r471",
      "r472",
      "r474"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.",
        "label": "Debt Disclosure [Text Block]",
        "terseLabel": "Debt"
       }
      }
     },
     "localname": "DebtDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebt"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_DebtInstrumentAxis": {
     "auth_ref": [
      "r1",
      "r2",
      "r3",
      "r217",
      "r221",
      "r235",
      "r300",
      "r448",
      "r449",
      "r450",
      "r451",
      "r452",
      "r454",
      "r460",
      "r461",
      "r462",
      "r463",
      "r465",
      "r466",
      "r467",
      "r468",
      "r469",
      "r470",
      "r691",
      "r792",
      "r793",
      "r794",
      "r795",
      "r796",
      "r847"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of debt instrument, including, but not limited to, draws against credit facilities.",
        "label": "Debt Instrument [Axis]",
        "terseLabel": "Debt Instrument"
       }
      }
     },
     "localname": "DebtInstrumentAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentBasisSpreadOnVariableRate1": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Percentage points added to the reference rate to compute the variable rate on the debt instrument.",
        "label": "Debt Instrument, Basis Spread on Variable Rate",
        "terseLabel": "Debt instrument, basis spread on variable rate"
       }
      }
     },
     "localname": "DebtInstrumentBasisSpreadOnVariableRate1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_DebtInstrumentCarryingAmount": {
     "auth_ref": [
      "r3",
      "r221",
      "r235",
      "r475"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_ConvertibleLongTermNotesPayable",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.",
        "label": "Long-Term Debt, Gross",
        "verboseLabel": "Principal"
       }
      }
     },
     "localname": "DebtInstrumentCarryingAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent": {
     "auth_ref": [
      "r123"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.",
        "label": "Debt Instrument, Convertible, Carrying Amount of Equity Component",
        "terseLabel": "Net carrying value of equity component of convertible notes"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentConvertibleConversionPrice1": {
     "auth_ref": [
      "r124",
      "r450"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The price per share of the conversion feature embedded in the debt instrument.",
        "label": "Debt Instrument, Convertible, Conversion Price",
        "terseLabel": "Debt instrument convertible initial conversion price per share of common stock"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleConversionPrice1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal": {
     "auth_ref": [
      "r125"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.",
        "label": "Debt Instrument, Convertible, If-converted Value in Excess of Principal",
        "terseLabel": "Debt instrument, convertible, \"if-converted value\" in excess of the principal amount"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentConvertibleTermsOfConversionFeature": {
     "auth_ref": [
      "r22",
      "r134",
      "r137",
      "r138"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Description of conversion terms for debt instrument.",
        "label": "Debt Instrument, Convertible, Terms of Conversion Feature",
        "terseLabel": "Debt instrument, convertible, terms of conversion feature"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleTermsOfConversionFeature",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.",
        "label": "Debt Instrument, Convertible, Threshold Consecutive Trading Days",
        "terseLabel": "Debt instrument, convertible, consecutive trading days"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleThresholdConsecutiveTradingDays1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.",
        "label": "Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger",
        "terseLabel": "Debt instrument, convertible, threshold percentage of conversion price"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_DebtInstrumentConvertibleThresholdTradingDays": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.",
        "label": "Debt Instrument, Convertible, Threshold Trading Days",
        "terseLabel": "Debt instrument, convertible, trading days"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleThresholdTradingDays",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "us-gaap_DebtInstrumentDescription": {
     "auth_ref": [
      "r1",
      "r3",
      "r134",
      "r217",
      "r221",
      "r229",
      "r235"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Identification of the lender and information about a contractual promise to repay a short-term or long-term obligation, which includes borrowings under lines of credit, notes payable, commercial paper, bonds payable, debentures, and other contractual obligations for payment. This may include rationale for entering into the arrangement, significant terms of the arrangement, which may include amount, repayment terms, priority, collateral required, debt covenants, borrowing capacity, call features, participation rights, conversion provisions, sinking-fund requirements, voting rights, basis for conversion if convertible and remarketing provisions. The description may be provided for individual debt instruments, rational groupings of debt instruments, or by debt in total.",
        "label": "Debt Instrument, Description",
        "terseLabel": "Debt instrument, description"
       }
      }
     },
     "localname": "DebtInstrumentDescription",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentFaceAmount": {
     "auth_ref": [
      "r211",
      "r213",
      "r448",
      "r691",
      "r793",
      "r794"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Face (par) amount of debt instrument at time of issuance.",
        "label": "Debt Instrument, Face Amount",
        "terseLabel": "Debt instrument, aggregate principal amount"
       }
      }
     },
     "localname": "DebtInstrumentFaceAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentFairValue": {
     "auth_ref": [
      "r462",
      "r658",
      "r793",
      "r794"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.",
        "label": "Debt Instrument, Fair Value Disclosure",
        "terseLabel": "Debt instrument, fair value of the liability component",
        "totalLabel": "Debt Instrument, Fair Value Disclosure, Total"
       }
      }
     },
     "localname": "DebtInstrumentFairValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentFrequencyOfPeriodicPayment": {
     "auth_ref": [
      "r23",
      "r230"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Description of the frequency of periodic payments (monthly, quarterly, annual).",
        "label": "Debt Instrument, Frequency of Periodic Payment",
        "terseLabel": "Debt instrument frequency of periodic payment"
       }
      }
     },
     "localname": "DebtInstrumentFrequencyOfPeriodicPayment",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentInterestRateStatedPercentage": {
     "auth_ref": [
      "r21",
      "r449"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Contractual interest rate for funds borrowed, under the debt agreement.",
        "label": "Debt Instrument, Interest Rate, Stated Percentage",
        "terseLabel": "Debt instrument interest rate"
       }
      }
     },
     "localname": "DebtInstrumentInterestRateStatedPercentage",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_DebtInstrumentLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Debt Instrument [Line Items]",
        "terseLabel": "Debt Instrument [Line Items]"
       }
      }
     },
     "localname": "DebtInstrumentLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentMaturityDate": {
     "auth_ref": [
      "r272",
      "r792",
      "r937"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.",
        "label": "Debt Instrument, Maturity Date",
        "terseLabel": "Debt instrument maturity date"
       }
      }
     },
     "localname": "DebtInstrumentMaturityDate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "dateItemType"
    },
    "us-gaap_DebtInstrumentNameDomain": {
     "auth_ref": [
      "r23",
      "r300",
      "r448",
      "r449",
      "r450",
      "r451",
      "r452",
      "r454",
      "r460",
      "r461",
      "r462",
      "r463",
      "r465",
      "r466",
      "r467",
      "r468",
      "r469",
      "r470",
      "r691",
      "r792",
      "r793",
      "r794",
      "r795",
      "r796",
      "r847"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The name for the particular debt instrument or borrowing that distinguishes it from other debt instruments or borrowings, including draws against credit facilities.",
        "label": "Debt Instrument, Name [Domain]",
        "terseLabel": "Debt Instrument, Name"
       }
      }
     },
     "localname": "DebtInstrumentNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DebtInstrumentRedemptionPricePercentage": {
     "auth_ref": [
      "r231"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.",
        "label": "Debt Instrument, Redemption Price, Percentage",
        "terseLabel": "Debt Instrument, Redemption Price, Percentage"
       }
      }
     },
     "localname": "DebtInstrumentRedemptionPricePercentage",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_DebtInstrumentRepurchasedFaceAmount": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Face (par) amount of the original debt instrument that was repurchased.",
        "label": "Debt Instrument, Repurchased Face Amount",
        "terseLabel": "Debt instrument repurchased face amount"
       }
      }
     },
     "localname": "DebtInstrumentRepurchasedFaceAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentTable": {
     "auth_ref": [
      "r23",
      "r134",
      "r137",
      "r138",
      "r139",
      "r210",
      "r211",
      "r213",
      "r232",
      "r300",
      "r448",
      "r449",
      "r450",
      "r451",
      "r452",
      "r454",
      "r460",
      "r461",
      "r462",
      "r463",
      "r465",
      "r466",
      "r467",
      "r468",
      "r469",
      "r470",
      "r473",
      "r691",
      "r792",
      "r793",
      "r794",
      "r795",
      "r796",
      "r847"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A table or schedule providing information pertaining to long-term debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the company, if longer.",
        "label": "Schedule of Long-Term Debt Instruments [Table]",
        "terseLabel": "Debt Instrument [Table]"
       }
      }
     },
     "localname": "DebtInstrumentTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentUnamortizedDiscount": {
     "auth_ref": [
      "r210",
      "r213",
      "r894"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_ConvertibleLongTermNotesPayable",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after accumulated amortization, of debt discount.",
        "label": "Debt Instrument, Unamortized Discount",
        "terseLabel": "Less: unamortized debt discount",
        "totalLabel": "Debt Instrument, Unamortized Discount, Total"
       }
      }
     },
     "localname": "DebtInstrumentUnamortizedDiscount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredFederalIncomeTaxExpenseBenefit": {
     "auth_ref": [
      "r849",
      "r930",
      "r931"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_DeferredIncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred federal tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, deferred national tax expense (benefit) for non-US (United States of America) jurisdiction.",
        "label": "Deferred Federal Income Tax Expense (Benefit)",
        "terseLabel": "U.S. Federal"
       }
      }
     },
     "localname": "DeferredFederalIncomeTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredFinanceCostsNet": {
     "auth_ref": [
      "r212",
      "r894"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_ConvertibleLongTermNotesPayable",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.",
        "label": "Debt Issuance Costs, Net",
        "terseLabel": "Less: unamortized debt issuance costs",
        "totalLabel": "Debt Issuance Costs, Net, Total"
       }
      }
     },
     "localname": "DeferredFinanceCostsNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfNetCarryingValueOfLiabilityComponentOf2027And2024NotesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredForeignIncomeTaxExpenseBenefit": {
     "auth_ref": [
      "r170",
      "r849",
      "r930"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_DeferredIncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.",
        "label": "Deferred Foreign Income Tax Expense (Benefit)",
        "terseLabel": "Non-U.S."
       }
      }
     },
     "localname": "DeferredForeignIncomeTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredIncomeTaxAssetsNet": {
     "auth_ref": [
      "r591",
      "r592"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 5.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.",
        "label": "Deferred Income Tax Assets, Net",
        "terseLabel": "Deferred tax assets"
       }
      }
     },
     "localname": "DeferredIncomeTaxAssetsNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredIncomeTaxExpenseBenefit": {
     "auth_ref": [
      "r65",
      "r170",
      "r609",
      "r618",
      "r619",
      "r849"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.",
        "label": "Deferred Income Tax Expense (Benefit)",
        "totalLabel": "Total deferred"
       }
      }
     },
     "localname": "DeferredIncomeTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredIncomeTaxLiabilities": {
     "auth_ref": [
      "r5",
      "r6",
      "r219",
      "r234",
      "r603"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_DeferredTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred tax liability attributable to taxable temporary differences.",
        "label": "Deferred Tax Liabilities, Gross",
        "totalLabel": "Total deferred tax liabilities"
       }
      }
     },
     "localname": "DeferredIncomeTaxLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredIncomeTaxLiabilitiesNet": {
     "auth_ref": [
      "r591",
      "r592"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_OtherLiabilitiesNoncurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.",
        "label": "Deferred Income Tax Liabilities, Net",
        "terseLabel": "Deferred tax liabilities"
       }
      }
     },
     "localname": "DeferredIncomeTaxLiabilitiesNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredIncomeTaxesAndTaxCredits": {
     "auth_ref": [
      "r66"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 4.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred income tax expense (benefit) and income tax credits.",
        "label": "Deferred Income Taxes and Tax Credits",
        "terseLabel": "Deferred income taxes",
        "totalLabel": "Deferred Income Taxes and Tax Credits, Total"
       }
      }
     },
     "localname": "DeferredIncomeTaxesAndTaxCredits",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit": {
     "auth_ref": [
      "r849",
      "r930",
      "r931"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_DeferredIncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred state and local tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, deferred regional, territorial, and provincial tax expense (benefit) for non-US (United States of America) jurisdiction.",
        "label": "Deferred State and Local Income Tax Expense (Benefit)",
        "terseLabel": "U.S. State and Local"
       }
      }
     },
     "localname": "DeferredStateAndLocalIncomeTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsDeferredIncome": {
     "auth_ref": [
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.",
        "label": "Deferred Tax Assets, Deferred Income",
        "terseLabel": "Deferred revenue"
       }
      }
     },
     "localname": "DeferredTaxAssetsDeferredIncome",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsGross": {
     "auth_ref": [
      "r604"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_DeferredTaxAssetsNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.",
        "label": "Deferred Tax Assets, Gross",
        "totalLabel": "Total gross deferred tax assets"
       }
      }
     },
     "localname": "DeferredTaxAssetsGross",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsInProcessResearchAndDevelopment": {
     "auth_ref": [
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 4.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.",
        "label": "Deferred Tax Assets, in Process Research and Development",
        "terseLabel": "Capitalized research and development"
       }
      }
     },
     "localname": "DeferredTaxAssetsInProcessResearchAndDevelopment",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsNet": {
     "auth_ref": [
      "r927"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail": {
       "order": 3.0,
       "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet",
       "weight": 1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_DeferredTaxLiabilities",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.",
        "label": "Deferred Tax Assets, Net of Valuation Allowance",
        "terseLabel": "Deferred tax assets",
        "totalLabel": "Net deferred tax assets"
       }
      }
     },
     "localname": "DeferredTaxAssetsNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsNetAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Deferred Tax Assets, Net [Abstract]",
        "terseLabel": "Deferred tax assets:"
       }
      }
     },
     "localname": "DeferredTaxAssetsNetAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DeferredTaxAssetsOperatingLossCarryforwards": {
     "auth_ref": [
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.",
        "label": "Deferred Tax Assets, Operating Loss Carryforwards",
        "terseLabel": "Net operating loss carryforwards",
        "totalLabel": "Deferred Tax Assets, Operating Loss Carryforwards, Total"
       }
      }
     },
     "localname": "DeferredTaxAssetsOperatingLossCarryforwards",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.",
        "label": "Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration",
        "terseLabel": "Credits and loss carryforwards"
       }
      }
     },
     "localname": "DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsTaxCreditCarryforwards": {
     "auth_ref": [
      "r166",
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.",
        "label": "Deferred Tax Assets, Tax Credit Carryforwards",
        "terseLabel": "Tax credit carryforwards",
        "totalLabel": "Deferred Tax Assets, Tax Credit Carryforwards, Total"
       }
      }
     },
     "localname": "DeferredTaxAssetsTaxCreditCarryforwards",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeign": {
     "auth_ref": [
      "r166",
      "r168",
      "r928"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign tax credit carryforwards.",
        "label": "Deferred Tax Assets, Tax Credit Carryforwards, Foreign",
        "terseLabel": "U.S. foreign tax credits"
       }
      }
     },
     "localname": "DeferredTaxAssetsTaxCreditCarryforwardsForeign",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits": {
     "auth_ref": [
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 6.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from employee benefits, classified as other.",
        "label": "Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits",
        "terseLabel": "Employee benefits"
       }
      }
     },
     "localname": "DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost": {
     "auth_ref": [
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 3.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.",
        "label": "Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-Based Compensation Cost",
        "terseLabel": "Stock-based compensation"
       }
      }
     },
     "localname": "DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsTaxDeferredExpenseOther": {
     "auth_ref": [
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 7.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from provisions, reserves, allowances, and accruals, classified as other.",
        "label": "Deferred Tax Assets, Tax Deferred Expense, Other",
        "terseLabel": "Other"
       }
      }
     },
     "localname": "DeferredTaxAssetsTaxDeferredExpenseOther",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsValuationAllowance": {
     "auth_ref": [
      "r605"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_DeferredTaxAssetsNet",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.",
        "label": "Deferred Tax Assets, Valuation Allowance",
        "negatedLabel": "Less: valuation allowances"
       }
      }
     },
     "localname": "DeferredTaxAssetsValuationAllowance",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxLiabilities": {
     "auth_ref": [
      "r159",
      "r927"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.",
        "label": "Deferred Tax Liabilities, Net",
        "negatedTotalLabel": "Total net deferred tax (liabilities) assets",
        "totalLabel": "Deferred Tax Liabilities, Net, Total"
       }
      }
     },
     "localname": "DeferredTaxLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxLiabilitiesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Deferred Tax Liabilities, Gross [Abstract]",
        "terseLabel": "Deferred tax liabilities:"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DeferredTaxLiabilitiesLeasingArrangements": {
     "auth_ref": [
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 3.0,
       "parentTag": "us-gaap_DeferredIncomeTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.",
        "label": "Deferred Tax Liabilities, Leasing Arrangements",
        "terseLabel": "Lease right of use asset"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesLeasingArrangements",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxLiabilitiesOther": {
     "auth_ref": [
      "r168",
      "r928"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail": {
       "order": 5.0,
       "parentTag": "us-gaap_DeferredIncomeTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of deferred tax liability attributable to taxable temporary differences classified as other.",
        "label": "Deferred Tax Liabilities, Other",
        "terseLabel": "Other"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesOther",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPensionPlanLiabilitiesCurrent": {
     "auth_ref": [
      "r2",
      "r142",
      "r143",
      "r144"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_DefinedBenefitPlanBenefitObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as current. Excludes other postretirement benefit plan.",
        "label": "Liability, Defined Benefit Pension Plan, Current",
        "terseLabel": "Accrued compensation and benefits"
       }
      }
     },
     "localname": "DefinedBenefitPensionPlanLiabilitiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent": {
     "auth_ref": [
      "r4",
      "r142",
      "r143",
      "r144"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_DefinedBenefitPlanBenefitObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan.",
        "label": "Liability, Defined Benefit Pension Plan, Noncurrent",
        "verboseLabel": "Other long-term liabilities"
       }
      }
     },
     "localname": "DefinedBenefitPensionPlanLiabilitiesNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation": {
     "auth_ref": [
      "r526"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.",
        "label": "Defined Benefit Plan, Accumulated Benefit Obligation",
        "terseLabel": "Accumulated benefit obligation"
       }
      }
     },
     "localname": "DefinedBenefitPlanAccumulatedBenefitObligation",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanBenefitObligation": {
     "auth_ref": [
      "r521"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.",
        "label": "Defined Benefit Plan, Benefit Obligation",
        "periodEndLabel": "Defined Benefit Plan, Benefit Obligation, Ending Balance",
        "periodStartLabel": "Defined Benefit Plan, Benefit Obligation, Beginning Balance",
        "terseLabel": "Defined benefit plan, benefit obligation",
        "totalLabel": "Components of pension benefits"
       }
      }
     },
     "localname": "DefinedBenefitPlanBenefitObligation",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfPensionBenefitsObligationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid": {
     "auth_ref": [
      "r522",
      "r538"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.",
        "label": "Defined Benefit Plan, Benefit Obligation, Benefits Paid",
        "terseLabel": "Benefit obligation benefits paid"
       }
      }
     },
     "localname": "DefinedBenefitPlanBenefitObligationBenefitsPaid",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Defined Benefit Plan, Expected Future Benefit Payment [Abstract]"
       }
      }
     },
     "localname": "DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter": {
     "auth_ref": [
      "r527"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.",
        "label": "Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years",
        "terseLabel": "Next five years"
       }
      }
     },
     "localname": "DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfEstimatedFutureBenefitPaymentsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths": {
     "auth_ref": [
      "r527"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.",
        "label": "Defined Benefit Plan, Expected Future Benefit Payment, Year One",
        "terseLabel": "December 31, 2023"
       }
      }
     },
     "localname": "DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfEstimatedFutureBenefitPaymentsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive": {
     "auth_ref": [
      "r527"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.",
        "label": "Defined Benefit Plan, Expected Future Benefit Payment, Year Five",
        "terseLabel": "December 31, 2027"
       }
      }
     },
     "localname": "DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfEstimatedFutureBenefitPaymentsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour": {
     "auth_ref": [
      "r527"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.",
        "label": "Defined Benefit Plan, Expected Future Benefit Payment, Year Four",
        "terseLabel": "December 31, 2026"
       }
      }
     },
     "localname": "DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfEstimatedFutureBenefitPaymentsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree": {
     "auth_ref": [
      "r527"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.",
        "label": "Defined Benefit Plan, Expected Future Benefit Payment, Year Three",
        "terseLabel": "December 31, 2025"
       }
      }
     },
     "localname": "DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfEstimatedFutureBenefitPaymentsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo": {
     "auth_ref": [
      "r527"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.",
        "label": "Defined Benefit Plan, Expected Future Benefit Payment, Year Two",
        "terseLabel": "December 31, 2024"
       }
      }
     },
     "localname": "DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsScheduleOfEstimatedFutureBenefitPaymentsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost": {
     "auth_ref": [
      "r528",
      "r535",
      "r806",
      "r807"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of net periodic benefit cost (credit) for defined benefit plan.",
        "label": "Defined Benefit Plan, Net Periodic Benefit Cost (Credit)",
        "terseLabel": "Net benefit cost",
        "totalLabel": "Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total"
       }
      }
     },
     "localname": "DefinedBenefitPlanNetPeriodicBenefitCost",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of discretionary contributions made by an employer to a defined contribution plan.",
        "label": "Defined Contribution Plan, Employer Discretionary Contribution Amount",
        "terseLabel": "Defined Benefit Plan, Contributions by Employer"
       }
      }
     },
     "localname": "DefinedContributionPlanEmployerDiscretionaryContributionAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.",
        "label": "Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent",
        "terseLabel": "Funded percentage"
       }
      }
     },
     "localname": "DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_Depreciation": {
     "auth_ref": [
      "r65",
      "r109"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.",
        "label": "Depreciation",
        "terseLabel": "Depreciation expense, including amortization of right-of-use assets under finance leases",
        "totalLabel": "Depreciation, Total"
       }
      }
     },
     "localname": "Depreciation",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DepreciationDepletionAndAmortization": {
     "auth_ref": [
      "r65",
      "r360"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail": {
       "order": 3.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": -1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 1.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.",
        "label": "Depreciation, Depletion and Amortization",
        "negatedLabel": "Depreciation and amortization",
        "terseLabel": "Depreciation and amortization",
        "totalLabel": "Depreciation, Depletion and Amortization, Total"
       }
      }
     },
     "localname": "DepreciationDepletionAndAmortization",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DerivativeContractTypeDomain": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Financial instrument or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.",
        "label": "Derivative Contract [Domain]",
        "terseLabel": "Derivative Contract"
       }
      }
     },
     "localname": "DerivativeContractTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DerivativeInstrumentRiskAxis": {
     "auth_ref": [
      "r194",
      "r195",
      "r197",
      "r198",
      "r785"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of derivative contract.",
        "label": "Derivative Instrument [Axis]",
        "terseLabel": "Derivative Instrument"
       }
      }
     },
     "localname": "DerivativeInstrumentRiskAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DerivativeNotionalAmount": {
     "auth_ref": [
      "r933",
      "r934"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Nominal or face amount used to calculate payment on derivative.",
        "label": "Derivative, Notional Amount",
        "terseLabel": "Derivatives outstanding notional value"
       }
      }
     },
     "localname": "DerivativeNotionalAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DevelopedTechnologyRightsMember": {
     "auth_ref": [
      "r181"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Rights to developed technology, which can include the right to develop, use, market, sell, or offer for sale products, compounds, or intellectual property.",
        "label": "Developed Technology Rights [Member]",
        "terseLabel": "Developed Technology [Member]"
       }
      }
     },
     "localname": "DevelopedTechnologyRightsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DisaggregationOfRevenueLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Disaggregation of Revenue [Line Items]",
        "terseLabel": "Disaggregation Of Revenue [Line Items]"
       }
      }
     },
     "localname": "DisaggregationOfRevenueLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DisaggregationOfRevenueTable": {
     "auth_ref": [
      "r516",
      "r798",
      "r799",
      "r800",
      "r801",
      "r802",
      "r803",
      "r804"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of information about disaggregation of revenue into categories depicting how nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factor.",
        "label": "Disaggregation of Revenue [Table]",
        "terseLabel": "Disaggregation Of Revenue [Table]"
       }
      }
     },
     "localname": "DisaggregationOfRevenueTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DisaggregationOfRevenueTableTextBlock": {
     "auth_ref": [
      "r896"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of disaggregation of revenue into categories depicting how nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factor.",
        "label": "Disaggregation of Revenue [Table Text Block]",
        "terseLabel": "Schedule of Disaggregation of Revenue"
       }
      }
     },
     "localname": "DisaggregationOfRevenueTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock": {
     "auth_ref": [
      "r546",
      "r577",
      "r578",
      "r580",
      "r585",
      "r811"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for share-based payment arrangement.",
        "label": "Share-Based Payment Arrangement [Text Block]",
        "terseLabel": "Stock-Based Compensation"
       }
      }
     },
     "localname": "DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensation"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Share-Based Payment Arrangement [Abstract]"
       }
      }
     },
     "localname": "DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_EMEAMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Regions of Europe, Middle East and Africa.",
        "label": "EMEA [Member]",
        "terseLabel": "Europe Middle East And Africa [Member]"
       }
      }
     },
     "localname": "EMEAMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_EarningsPerShareAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Earnings Per Share [Abstract]",
        "terseLabel": "Loss per share:"
       }
      }
     },
     "localname": "EarningsPerShareAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_EarningsPerShareBasic": {
     "auth_ref": [
      "r285",
      "r317",
      "r318",
      "r319",
      "r320",
      "r321",
      "r327",
      "r329",
      "r336",
      "r337",
      "r338",
      "r342",
      "r654",
      "r655",
      "r735",
      "r741",
      "r788"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.",
        "label": "Earnings Per Share, Basic",
        "terseLabel": "Net loss per share attributable to common stockholders, basic",
        "totalLabel": "Earnings Per Share, Basic, Total"
       }
      }
     },
     "localname": "EarningsPerShareBasic",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_EarningsPerShareBasicLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]",
        "terseLabel": "Earnings Per Share Basic [Line Items]"
       }
      }
     },
     "localname": "EarningsPerShareBasicLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_EarningsPerShareDiluted": {
     "auth_ref": [
      "r285",
      "r317",
      "r318",
      "r319",
      "r320",
      "r321",
      "r329",
      "r336",
      "r337",
      "r338",
      "r342",
      "r654",
      "r655",
      "r735",
      "r741",
      "r788"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.",
        "label": "Earnings Per Share, Diluted",
        "terseLabel": "Net loss per share attributable to common stockholders, diluted",
        "totalLabel": "Earnings Per Share, Diluted, Total"
       }
      }
     },
     "localname": "EarningsPerShareDiluted",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_EarningsPerShareTextBlock": {
     "auth_ref": [
      "r339",
      "r340",
      "r341",
      "r343"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for earnings per share.",
        "label": "Earnings Per Share [Text Block]",
        "terseLabel": "Net Loss Per Share"
       }
      }
     },
     "localname": "EarningsPerShareTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShare"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents": {
     "auth_ref": [
      "r674"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 3.0,
       "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase (decrease) from effect of exchange rate changes on cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; held in foreign currencies. Excludes amounts for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.",
        "label": "Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations",
        "terseLabel": "Effect of exchange rate changes on cash, cash equivalents and restricted cash"
       }
      }
     },
     "localname": "EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate": {
     "auth_ref": [
      "r298",
      "r594",
      "r621"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Percentage of domestic federal statutory tax rate applicable to pretax income (loss).",
        "label": "Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent",
        "terseLabel": "U.S. Federal statutory income tax rate",
        "verboseLabel": "U.S. federal statutory rate"
       }
      }
     },
     "localname": "EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_EffectiveIncomeTaxRateReconciliationFdiiAmount": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 12.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of reported income tax benefit from difference to expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to foreign-derived intangible income (FDII).",
        "label": "Effective Income Tax Rate Reconciliation, FDII, Amount",
        "negatedLabel": "FDII deduction",
        "terseLabel": "FDII deduction"
       }
      }
     },
     "localname": "EffectiveIncomeTaxRateReconciliationFdiiAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Amount": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 4.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to Tax Cuts and Jobs Act.",
        "label": "Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Amount",
        "terseLabel": "U.S. effect of foreign operations"
       }
      }
     },
     "localname": "EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Amount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_EmployeeRelatedLiabilitiesCurrent": {
     "auth_ref": [
      "r19"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_LiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).",
        "label": "Employee-related Liabilities, Current",
        "terseLabel": "Accrued compensation and benefits",
        "totalLabel": "Employee-related Liabilities, Current, Total"
       }
      }
     },
     "localname": "EmployeeRelatedLiabilitiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_EmployeeServiceShareBasedCompensationAggregateDisclosuresAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Share-Based Payment Arrangement, Additional Disclosure [Abstract]"
       }
      }
     },
     "localname": "EmployeeServiceShareBasedCompensationAggregateDisclosuresAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]",
        "terseLabel": "Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]"
       }
      }
     },
     "localname": "EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized": {
     "auth_ref": [
      "r579"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cost not yet recognized for nonvested award under share-based payment arrangement.",
        "label": "Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount",
        "terseLabel": "Compensation cost related to nonvested awards not yet recognized",
        "totalLabel": "Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total"
       }
      }
     },
     "localname": "EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1": {
     "auth_ref": [
      "r579"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition",
        "terseLabel": "Weighted average period of recognition"
       }
      }
     },
     "localname": "EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_EquityAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Equity [Abstract]"
       }
      }
     },
     "localname": "EquityAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_EquityComponentDomain": {
     "auth_ref": [
      "r133",
      "r252",
      "r279",
      "r280",
      "r281",
      "r308",
      "r309",
      "r310",
      "r314",
      "r322",
      "r324",
      "r344",
      "r401",
      "r493",
      "r581",
      "r582",
      "r583",
      "r613",
      "r614",
      "r653",
      "r675",
      "r676",
      "r677",
      "r678",
      "r679",
      "r682",
      "r718",
      "r746",
      "r747",
      "r748"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Components of equity are the parts of the total Equity balance including that which is allocated to common, preferred, treasury stock, retained earnings, etc.",
        "label": "Equity Component [Domain]",
        "terseLabel": "Equity Component"
       }
      }
     },
     "localname": "EquityComponentDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_EscrowDeposit": {
     "auth_ref": [
      "r223",
      "r767"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.",
        "label": "Escrow Deposit",
        "terseLabel": "Escrow deposit"
       }
      }
     },
     "localname": "EscrowDeposit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain": {
     "auth_ref": [
      "r203"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Class of asset.",
        "label": "Asset Class [Domain]",
        "terseLabel": "Asset Class"
       }
      }
     },
     "localname": "FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]",
        "terseLabel": "Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]"
       }
      }
     },
     "localname": "FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueByAssetClassAxis": {
     "auth_ref": [
      "r202",
      "r204"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by class of asset.",
        "label": "Asset Class [Axis]",
        "terseLabel": "Asset Class"
       }
      }
     },
     "localname": "FairValueByAssetClassAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueByBalanceSheetGroupingTable": {
     "auth_ref": [
      "r202",
      "r205",
      "r206"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of information about the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.",
        "label": "Fair Value, by Balance Sheet Grouping [Table]",
        "terseLabel": "Fair Value By Balance Sheet Grouping [Table]"
       }
      }
     },
     "localname": "FairValueByBalanceSheetGroupingTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueDisclosuresAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Fair Value Disclosures [Abstract]"
       }
      }
     },
     "localname": "FairValueDisclosuresAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueDisclosuresTextBlock": {
     "auth_ref": [
      "r657"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.",
        "label": "Fair Value Disclosures [Text Block]",
        "terseLabel": "Fair Value Measurements"
       }
      }
     },
     "localname": "FairValueDisclosuresTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurements"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_FederalFundsEffectiveSwapRateMember": {
     "auth_ref": [
      "r935"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Fixed rate on U.S. dollar, constant-notional interest rate swap having its variable-rate leg referenced to Federal Funds effective rate with no additional spread over Federal Funds effective rate on that variable-rate leg.",
        "label": "Fed Funds Effective Rate Overnight Index Swap Rate [Member]",
        "terseLabel": "Federal Funds Effective Swap Rate [Member]"
       }
      }
     },
     "localname": "FederalFundsEffectiveSwapRateMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FinanceLeaseInterestExpense": {
     "auth_ref": [
      "r700",
      "r706",
      "r818"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail": {
       "order": 1.0,
       "parentTag": "altr_FinanceLeaseCost",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of interest expense on finance lease liability.",
        "label": "Finance Lease, Interest Expense",
        "terseLabel": "Interest on lease liabilities"
       }
      }
     },
     "localname": "FinanceLeaseInterestExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseInterestPaymentOnLiability": {
     "auth_ref": [
      "r702",
      "r708"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of interest paid on finance lease liability.",
        "label": "Finance Lease, Interest Payment on Liability",
        "negatedLabel": "Operating cash flows from finance leases"
       }
      }
     },
     "localname": "FinanceLeaseInterestPaymentOnLiability",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalCashFlowInformationRelatedToLeasesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiability": {
     "auth_ref": [
      "r698",
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Present value of lessee's discounted obligation for lease payments from finance lease.",
        "label": "Finance Lease, Liability",
        "totalLabel": "Total finance lease liabilities"
       }
      }
     },
     "localname": "FinanceLeaseLiability",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityCurrent": {
     "auth_ref": [
      "r698"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_FinanceLeaseLiability",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.",
        "label": "Finance Lease, Liability, Current",
        "terseLabel": "Other accrued expenses and current liabilities"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList": {
     "auth_ref": [
      "r699"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicates line item in statement of financial position that includes current finance lease liability.",
        "label": "Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]",
        "terseLabel": "Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "enumerationSetItemType"
    },
    "us-gaap_FinanceLeaseLiabilityNoncurrent": {
     "auth_ref": [
      "r698"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_FinanceLeaseLiability",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.",
        "label": "Finance Lease, Liability, Noncurrent",
        "terseLabel": "Other long-term liabilities"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList": {
     "auth_ref": [
      "r699"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicates line item in statement of financial position that includes noncurrent finance lease liability.",
        "label": "Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]",
        "terseLabel": "Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "enumerationSetItemType"
    },
    "us-gaap_FinanceLeasePrincipalPayments": {
     "auth_ref": [
      "r701",
      "r708"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash outflow for principal payment on finance lease.",
        "label": "Finance Lease, Principal Payments",
        "negatedLabel": "Financing cash flows from finance leases"
       }
      }
     },
     "localname": "FinanceLeasePrincipalPayments",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalCashFlowInformationRelatedToLeasesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseRightOfUseAsset": {
     "auth_ref": [
      "r697"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after accumulated amortization, of right-of-use asset from finance lease.",
        "label": "Finance Lease, Right-of-Use Asset, after Accumulated Amortization",
        "totalLabel": "Property and equipment, net"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAsset",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseRightOfUseAssetAmortization": {
     "auth_ref": [
      "r700",
      "r706",
      "r818"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail": {
       "order": 0.0,
       "parentTag": "altr_FinanceLeaseCost",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of amortization expense attributable to right-of-use asset from finance lease.",
        "label": "Finance Lease, Right-of-Use Asset, Amortization",
        "terseLabel": "Amortization of ROU assets"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAssetAmortization",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList": {
     "auth_ref": [
      "r699"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Indicates line item in statement of financial position that includes finance lease right-of-use asset.",
        "label": "Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]",
        "terseLabel": "Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "enumerationSetItemType"
    },
    "us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent": {
     "auth_ref": [
      "r711",
      "r818"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average discount rate for finance lease calculated at point in time.",
        "label": "Finance Lease, Weighted Average Discount Rate, Percent",
        "terseLabel": "Weighted average discount rate"
       }
      }
     },
     "localname": "FinanceLeaseWeightedAverageDiscountRatePercent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_FinanceLeaseWeightedAverageRemainingLeaseTerm1": {
     "auth_ref": [
      "r710",
      "r818"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Finance Lease, Weighted Average Remaining Lease Term",
        "terseLabel": "Weighted average remaining lease term"
       }
      }
     },
     "localname": "FinanceLeaseWeightedAverageRemainingLeaseTerm1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization": {
     "auth_ref": [
      "r263",
      "r422"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_IntangibleAssetsNetExcludingGoodwill",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.",
        "label": "Finite-Lived Intangible Assets, Accumulated Amortization",
        "terseLabel": "Accumulated amortization"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAccumulatedAmortization",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_FiniteLivedIntangibleAssetsNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.",
        "label": "Finite-Lived Intangible Assets, Amortization Expense, Next Rolling 12 Months",
        "terseLabel": "December 31, 2023"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseNextRollingTwelveMonths",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingAfterYearFive": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail": {
       "order": 5.0,
       "parentTag": "us-gaap_FiniteLivedIntangibleAssetsNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.",
        "label": "Finite-Lived Intangible Assets, Amortization Expense, Rolling after Year Five",
        "terseLabel": "Thereafter"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseRollingAfterYearFive",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFive": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail": {
       "order": 4.0,
       "parentTag": "us-gaap_FiniteLivedIntangibleAssetsNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.",
        "label": "Finite-Lived Intangible Assets, Amortization Expense, Rolling Year Five",
        "terseLabel": "December 31, 2027"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFive",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFour": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail": {
       "order": 3.0,
       "parentTag": "us-gaap_FiniteLivedIntangibleAssetsNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the fourth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.",
        "label": "Finite-Lived Intangible Assets, Amortization Expense, Rolling Year Four",
        "terseLabel": "December 31, 2026"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearFour",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearThree": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_FiniteLivedIntangibleAssetsNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the third rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.",
        "label": "Finite-Lived Intangible Assets, Amortization Expense, Rolling Year Three",
        "terseLabel": "December 31, 2025"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearThree",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearTwo": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_FiniteLivedIntangibleAssetsNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the second rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.",
        "label": "Finite-Lived Intangible Assets, Amortization Expense, Rolling Year Two",
        "terseLabel": "December 31, 2024"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseRollingYearTwo",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis": {
     "auth_ref": [
      "r419",
      "r421",
      "r422",
      "r424",
      "r727",
      "r731"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by major type or class of finite-lived intangible assets.",
        "label": "Finite-Lived Intangible Assets by Major Class [Axis]",
        "terseLabel": "Finite-Lived Intangible Assets by Major Class"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsByMajorClassAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsGross": {
     "auth_ref": [
      "r99",
      "r731"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_FiniteLivedIntangibleAssetsNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.",
        "label": "Finite-Lived Intangible Assets, Gross",
        "terseLabel": "Gross carrying amount",
        "totalLabel": "Finite-Lived Intangible Assets, Gross, Total"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsGross",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain": {
     "auth_ref": [
      "r94",
      "r98"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The major class of finite-lived intangible asset (for example, patents, trademarks, copyrights, etc.) A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.",
        "label": "Finite-Lived Intangible Assets, Major Class Name [Domain]",
        "terseLabel": "Finite-Lived Intangible Assets, Major Class Name"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsMajorClassNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsNet": {
     "auth_ref": [
      "r99",
      "r727"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.",
        "label": "Finite-Lived Intangible Assets, Net",
        "periodEndLabel": "Finite-Lived Intangible Assets, Net, Ending Balance",
        "periodStartLabel": "Finite-Lived Intangible Assets, Net, Beginning Balance",
        "terseLabel": "Total",
        "totalLabel": "Net carrying amount"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ForeignCountryMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Designated tax departments of governments entitled to levy and collect income taxes from the entity outside the entity's country of domicile.",
        "label": "Foreign Tax Authority [Member]",
        "terseLabel": "Foreign Tax Authority [Member]"
       }
      }
     },
     "localname": "ForeignCountryMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ForeignCurrencyTransactionGainLossBeforeTax": {
     "auth_ref": [
      "r669",
      "r670",
      "r671",
      "r673"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_NonoperatingIncomeExpense",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.",
        "label": "Foreign Currency Transaction Gain (Loss), before Tax",
        "negatedLabel": "Foreign exchange loss (gain)",
        "totalLabel": "Foreign Currency Transaction Gain (Loss), before Tax, Total"
       }
      }
     },
     "localname": "ForeignCurrencyTransactionGainLossBeforeTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock": {
     "auth_ref": [
      "r684"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for (1) transactions denominated in a currency other than the reporting enterprise's functional currency, (2) translating foreign currency financial statements that are incorporated into the financial statements of the reporting enterprise by consolidation, combination, or the equity method of accounting, and (3) remeasurement of the financial statements of a foreign reporting enterprise in a hyperinflationary economy.",
        "label": "Foreign Currency Transactions and Translations Policy [Policy Text Block]",
        "terseLabel": "Foreign currency translation"
       }
      }
     },
     "localname": "ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ForeignExchangeContractMember": {
     "auth_ref": [
      "r785",
      "r805",
      "r817"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Derivative instrument whose primary underlying risk is tied to foreign exchange rates.",
        "label": "Foreign Exchange Contract [Member]",
        "terseLabel": "Foreign Exchange Contract [Member]"
       }
      }
     },
     "localname": "ForeignExchangeContractMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_GainLossRelatedToLitigationSettlement": {
     "auth_ref": [
      "r882"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.",
        "label": "Gain (Loss) Related to Litigation Settlement",
        "terseLabel": "Proceeds from settlements related to historical acquisition"
       }
      }
     },
     "localname": "GainLossRelatedToLitigationSettlement",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GeneralAndAdministrativeExpense": {
     "auth_ref": [
      "r48"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 2.0,
       "parentTag": "us-gaap_OperatingExpenses",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.",
        "label": "General and Administrative Expense",
        "terseLabel": "General and administrative",
        "totalLabel": "General and Administrative Expense, Total"
       }
      }
     },
     "localname": "GeneralAndAdministrativeExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GeneralAndAdministrativeExpenseMember": {
     "auth_ref": [
      "r43"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Primary financial statement caption encompassing general and administrative expense.",
        "label": "General and Administrative Expense [Member]",
        "terseLabel": "General and Administrative [Member]"
       }
      }
     },
     "localname": "GeneralAndAdministrativeExpenseMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_GeneralBusinessMember": {
     "auth_ref": [
      "r167"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tax credit carryforwards which include, but are not limited to, investment, alcohol fuels, low income housing, alternative fuels, alternative motor vehicles, hurricane relief, disabled access, renewable resources electricity production, employer social security, orphan drug, new markets, employer provided child care facilities and services, biodiesel fuels, low sulfur diesel fuel production, distilled spirits and the advanced nuclear power facilities credit.",
        "label": "General Business Tax Credit Carryforward [Member]",
        "terseLabel": "General Business Tax Credit Carryforward [Member]"
       }
      }
     },
     "localname": "GeneralBusinessMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_Goodwill": {
     "auth_ref": [
      "r262",
      "r409",
      "r732",
      "r791",
      "r819",
      "r867",
      "r874"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.",
        "label": "Goodwill",
        "periodEndLabel": "Ending Balance",
        "periodStartLabel": "Beginning Balance",
        "terseLabel": "Goodwill",
        "totalLabel": "Goodwill, Total"
       }
      }
     },
     "localname": "Goodwill",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsChangesInCarryingAmountOfGoodwillAttributableToSoftwareReportableSegmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GoodwillAcquiredDuringPeriod": {
     "auth_ref": [
      "r411",
      "r791"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.",
        "label": "Goodwill, Acquired During Period",
        "terseLabel": "Acquisitions"
       }
      }
     },
     "localname": "GoodwillAcquiredDuringPeriod",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsChangesInCarryingAmountOfGoodwillAttributableToSoftwareReportableSegmentDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Goodwill and Intangible Assets Disclosure [Abstract]"
       }
      }
     },
     "localname": "GoodwillAndIntangibleAssetsDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock": {
     "auth_ref": [
      "r104"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for goodwill and intangible assets.",
        "label": "Goodwill and Intangible Assets Disclosure [Text Block]",
        "terseLabel": "Goodwill and Other Intangible Assets"
       }
      }
     },
     "localname": "GoodwillAndIntangibleAssetsDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssets"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsIndefiniteLivedPolicy": {
     "auth_ref": [
      "r101"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for indefinite-lived intangible assets (that is, those intangible assets not subject to amortization). This accounting policy also may address how the entity assesses whether events and circumstances continue to support an indefinite useful life and how the entity assesses and measures impairment of such assets.",
        "label": "Goodwill and Intangible Assets, Intangible Assets, Indefinite-Lived, Policy [Policy Text Block]",
        "terseLabel": "Goodwill and other indefinite-lived intangible assets"
       }
      }
     },
     "localname": "GoodwillAndIntangibleAssetsIntangibleAssetsIndefiniteLivedPolicy",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_GoodwillMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.",
        "label": "Goodwill [Member]",
        "terseLabel": "Goodwill [Member]"
       }
      }
     },
     "localname": "GoodwillMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_GovernmentAssistancePolicyTextBlock": {
     "auth_ref": [
      "r685",
      "r686"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for government assistance.",
        "label": "Government Assistance [Policy Text Block]",
        "terseLabel": "Government assistance"
       }
      }
     },
     "localname": "GovernmentAssistancePolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_GranteeStatusAxis": {
     "auth_ref": [
      "r542",
      "r544",
      "r547",
      "r548",
      "r549",
      "r551",
      "r552",
      "r553",
      "r554",
      "r555",
      "r556",
      "r557",
      "r558",
      "r559",
      "r560",
      "r561",
      "r562",
      "r563",
      "r564",
      "r565",
      "r566",
      "r567",
      "r568",
      "r571",
      "r572",
      "r573",
      "r574",
      "r575"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by status of recipient to whom award is granted.",
        "label": "Grantee Status [Axis]",
        "terseLabel": "Grantee Status"
       }
      }
     },
     "localname": "GranteeStatusAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_GranteeStatusDomain": {
     "auth_ref": [
      "r542",
      "r544",
      "r547",
      "r548",
      "r549",
      "r551",
      "r552",
      "r553",
      "r554",
      "r555",
      "r556",
      "r557",
      "r558",
      "r559",
      "r560",
      "r561",
      "r562",
      "r563",
      "r564",
      "r565",
      "r566",
      "r567",
      "r568",
      "r571",
      "r572",
      "r573",
      "r574",
      "r575"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Status of recipient to whom award is granted.",
        "label": "Grantee Status [Domain]",
        "terseLabel": "Grantee Status"
       }
      }
     },
     "localname": "GranteeStatusDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_GrossProfit": {
     "auth_ref": [
      "r45",
      "r296",
      "r365",
      "r370",
      "r376",
      "r379",
      "r394",
      "r439",
      "r440",
      "r441",
      "r442",
      "r443",
      "r444",
      "r445",
      "r446",
      "r447",
      "r659",
      "r790",
      "r889"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 0.0,
       "parentTag": "us-gaap_OperatingIncomeLoss",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.",
        "label": "Gross Profit",
        "totalLabel": "Gross profit"
       }
      }
     },
     "localname": "GrossProfit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill": {
     "auth_ref": [
      "r845",
      "r878"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.",
        "label": "Impairment of Intangible Assets, Indefinite-Lived (Excluding Goodwill)",
        "terseLabel": "Impairment charge of indefinite-lived intangible assets"
       }
      }
     },
     "localname": "ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock": {
     "auth_ref": [
      "r105",
      "r113"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for recognizing and measuring the impairment of long-lived assets. An entity also may disclose its accounting policy for long-lived assets to be sold. This policy excludes goodwill and intangible assets.",
        "label": "Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]",
        "terseLabel": "Impairment of long-lived assets"
       }
      }
     },
     "localname": "ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic": {
     "auth_ref": [
      "r297",
      "r620"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfIncomeLossBeforeIncomeTaxesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.",
        "label": "Income (Loss) from Continuing Operations before Income Taxes, Domestic",
        "terseLabel": "U.S"
       }
      }
     },
     "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfIncomeLossBeforeIncomeTaxesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest": {
     "auth_ref": [
      "r41",
      "r214",
      "r226",
      "r248",
      "r365",
      "r370",
      "r376",
      "r379",
      "r736",
      "r790"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfIncomeLossBeforeIncomeTaxesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 0.0,
       "parentTag": "us-gaap_NetIncomeLoss",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.",
        "label": "Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest",
        "terseLabel": "(Loss) income before income taxes",
        "totalLabel": "(Loss) income before income taxes"
       }
      }
     },
     "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfIncomeLossBeforeIncomeTaxesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign": {
     "auth_ref": [
      "r297",
      "r620"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfIncomeLossBeforeIncomeTaxesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.",
        "label": "Income (Loss) from Continuing Operations before Income Taxes, Foreign",
        "terseLabel": "Non-U.S"
       }
      }
     },
     "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfIncomeLossBeforeIncomeTaxesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeStatementAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Income Statement [Abstract]"
       }
      }
     },
     "localname": "IncomeStatementAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncomeStatementLocationAxis": {
     "auth_ref": [
      "r425",
      "r427"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by location in the income statement.",
        "label": "Income Statement Location [Axis]",
        "terseLabel": "Income Statement Location"
       }
      }
     },
     "localname": "IncomeStatementLocationAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncomeStatementLocationDomain": {
     "auth_ref": [
      "r427"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Location in the income statement.",
        "label": "Income Statement Location [Domain]",
        "terseLabel": "Income Statement Location"
       }
      }
     },
     "localname": "IncomeStatementLocationDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_IncomeTaxAuthorityAxis": {
     "auth_ref": [
      "r162"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by tax jurisdiction.",
        "label": "Income Tax Authority [Axis]",
        "terseLabel": "Income Tax Authority"
       }
      }
     },
     "localname": "IncomeTaxAuthorityAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncomeTaxAuthorityDomain": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Agency, division or body classification that levies income taxes, examines tax returns for compliance, or grants exemptions from or makes other decisions pertaining to income taxes.",
        "label": "Income Tax Authority [Domain]",
        "terseLabel": "Income Tax Authority"
       }
      }
     },
     "localname": "IncomeTaxAuthorityDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_IncomeTaxAuthorityNameAxis": {
     "auth_ref": [
      "r162"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by name of taxing authority.",
        "label": "Income Tax Authority, Name [Axis]",
        "terseLabel": "Income Tax Authority, Name"
       }
      }
     },
     "localname": "IncomeTaxAuthorityNameAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncomeTaxAuthorityNameDomain": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Named agency, division or body that levies income taxes, examines tax returns for compliance, or grants exemptions from or makes other decisions pertaining to income taxes.",
        "label": "Income Tax Authority, Name [Domain]",
        "terseLabel": "Income Tax Authority, Name"
       }
      }
     },
     "localname": "IncomeTaxAuthorityNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_IncomeTaxDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Income Tax Disclosure [Abstract]"
       }
      }
     },
     "localname": "IncomeTaxDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncomeTaxDisclosureTextBlock": {
     "auth_ref": [
      "r298",
      "r595",
      "r601",
      "r607",
      "r616",
      "r622",
      "r626",
      "r627",
      "r628"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.",
        "label": "Income Tax Disclosure [Text Block]",
        "terseLabel": "Income Taxes"
       }
      }
     },
     "localname": "IncomeTaxDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxes"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_IncomeTaxExpenseBenefit": {
     "auth_ref": [
      "r299",
      "r323",
      "r324",
      "r363",
      "r593",
      "r617",
      "r624",
      "r742"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 1.0,
       "parentTag": "us-gaap_NetIncomeLoss",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.",
        "label": "Income Tax Expense (Benefit)",
        "terseLabel": "Income tax expense",
        "totalLabel": "Income tax expense"
       }
      }
     },
     "localname": "IncomeTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfIncomeTaxExpenseDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxPolicyTextBlock": {
     "auth_ref": [
      "r278",
      "r589",
      "r590",
      "r601",
      "r602",
      "r606",
      "r610"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.",
        "label": "Income Tax, Policy [Policy Text Block]",
        "terseLabel": "Income taxes"
       }
      }
     },
     "localname": "IncomeTaxPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_IncomeTaxReceivable": {
     "auth_ref": [
      "r233",
      "r835"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.",
        "label": "Income Taxes Receivable",
        "terseLabel": "Income tax receivable"
       }
      }
     },
     "localname": "IncomeTaxReceivable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 5.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.",
        "label": "Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount",
        "terseLabel": "Change in valuation allowance"
       }
      }
     },
     "localname": "IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit).",
        "label": "Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount",
        "terseLabel": "Foreign income taxes at rates other than the federal statutory rate"
       }
      }
     },
     "localname": "IncomeTaxReconciliationForeignIncomeTaxRateDifferential",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate": {
     "auth_ref": [
      "r594"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.",
        "label": "Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount",
        "terseLabel": "Income taxes at U.S. federal statutory rate"
       }
      }
     },
     "localname": "IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 9.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.",
        "label": "Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Amount",
        "terseLabel": "Stock-based compensation"
       }
      }
     },
     "localname": "IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationOtherAdjustments": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 10.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.",
        "label": "Effective Income Tax Rate Reconciliation, Other Adjustments, Amount",
        "terseLabel": "Other"
       }
      }
     },
     "localname": "IncomeTaxReconciliationOtherAdjustments",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax expense (benefit).",
        "label": "Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount",
        "terseLabel": "U.S. state and local income taxes, net of U.S. federal tax benefit"
       }
      }
     },
     "localname": "IncomeTaxReconciliationStateAndLocalIncomeTaxes",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationTaxContingenciesOther": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 11.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in other income tax contingencies.",
        "label": "Effective Income Tax Rate Reconciliation, Tax Contingency, Other, Amount",
        "terseLabel": "Uncertain tax positions"
       }
      }
     },
     "localname": "IncomeTaxReconciliationTaxContingenciesOther",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationTaxCreditsForeign": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 7.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign tax credit.",
        "label": "Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Amount",
        "negatedLabel": "U.S. foreign tax credit and deduction"
       }
      }
     },
     "localname": "IncomeTaxReconciliationTaxCreditsForeign",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationTaxCreditsResearch": {
     "auth_ref": [
      "r925"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail": {
       "order": 8.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit.",
        "label": "Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount",
        "negatedLabel": "Research and development tax credit"
       }
      }
     },
     "localname": "IncomeTaxReconciliationTaxCreditsResearch",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfIncomeTaxesCalculatedAtUSFederalStatutoryIncomeTaxRateDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxesPaid": {
     "auth_ref": [
      "r62",
      "r68"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.",
        "label": "Income Taxes Paid",
        "terseLabel": "Income taxes paid"
       }
      }
     },
     "localname": "IncomeTaxesPaid",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxesReceivable": {
     "auth_ref": [
      "r223",
      "r246",
      "r835"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_AssetsCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.",
        "label": "Income Taxes Receivable, Current",
        "terseLabel": "Income tax receivable",
        "verboseLabel": "Income tax receivable, current"
       }
      }
     },
     "localname": "IncomeTaxesReceivable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxesReceivableNoncurrent": {
     "auth_ref": [
      "r236",
      "r834"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.",
        "label": "Income Taxes Receivable, Noncurrent",
        "terseLabel": "Income tax receivable, noncurrent"
       }
      }
     },
     "localname": "IncomeTaxesReceivableNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInAccountsPayable": {
     "auth_ref": [
      "r64"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 11.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.",
        "label": "Increase (Decrease) in Accounts Payable",
        "terseLabel": "Accounts payable",
        "totalLabel": "Increase (Decrease) in Accounts Payable, Total"
       }
      }
     },
     "localname": "IncreaseDecreaseInAccountsPayable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInAccountsReceivable": {
     "auth_ref": [
      "r64"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 8.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.",
        "label": "Increase (Decrease) in Accounts Receivable",
        "negatedLabel": "Accounts receivable"
       }
      }
     },
     "localname": "IncreaseDecreaseInAccountsReceivable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInContractWithCustomerLiability": {
     "auth_ref": [
      "r725",
      "r844"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 14.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.",
        "label": "Increase (Decrease) in Contract with Customer, Liability",
        "terseLabel": "Deferred revenue"
       }
      }
     },
     "localname": "IncreaseDecreaseInContractWithCustomerLiability",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities": {
     "auth_ref": [
      "r64"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 12.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The increase (decrease) during the reporting period in the aggregate amount of obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits.",
        "label": "Increase (Decrease) in Employee Related Liabilities",
        "terseLabel": "Accrued compensation and benefits",
        "totalLabel": "Increase (Decrease) in Employee Related Liabilities, Total"
       }
      }
     },
     "localname": "IncreaseDecreaseInEmployeeRelatedLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInOperatingCapitalAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Increase (Decrease) in Operating Capital [Abstract]",
        "terseLabel": "Changes in assets and liabilities:"
       }
      }
     },
     "localname": "IncreaseDecreaseInOperatingCapitalAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncreaseDecreaseInOtherNoncurrentAssets": {
     "auth_ref": [
      "r844"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 10.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase (decrease) in noncurrent assets classified as other.",
        "label": "Increase (Decrease) in Other Noncurrent Assets",
        "negatedLabel": "Other long-term assets"
       }
      }
     },
     "localname": "IncreaseDecreaseInOtherNoncurrentAssets",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInOtherOperatingLiabilities": {
     "auth_ref": [
      "r64"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 13.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase (decrease) in operating liabilities classified as other.",
        "label": "Increase (Decrease) in Other Operating Liabilities",
        "terseLabel": "Other accrued expenses and current liabilities",
        "totalLabel": "Increase (Decrease) in Other Operating Liabilities, Total"
       }
      }
     },
     "localname": "IncreaseDecreaseInOtherOperatingLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets": {
     "auth_ref": [
      "r64"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 9.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase (decrease) in prepaid expenses, and assets classified as other.",
        "label": "Increase (Decrease) in Prepaid Expense and Other Assets",
        "negatedLabel": "Prepaid expenses and other current assets"
       }
      }
     },
     "localname": "IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements": {
     "auth_ref": [
      "r330",
      "r331",
      "r332",
      "r338",
      "r545"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding",
       "weight": 1.0
      }
     },
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.",
        "label": "Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements",
        "terseLabel": "Effect of dilutive securities, stock options and RSUs"
       }
      }
     },
     "localname": "IncrementalCommonSharesAttributableToShareBasedPaymentArrangements",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis": {
     "auth_ref": [
      "r420",
      "r423"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type or class of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.",
        "label": "Indefinite-Lived Intangible Assets [Axis]",
        "terseLabel": "Indefinite-lived Intangible Assets"
       }
      }
     },
     "localname": "IndefiniteLivedIntangibleAssetsByMajorClassAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill": {
     "auth_ref": [
      "r101"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.",
        "label": "Indefinite-Lived Intangible Assets (Excluding Goodwill)",
        "periodEndLabel": "Indefinite-Lived Intangible Assets (Excluding Goodwill), Ending Balance",
        "periodStartLabel": "Indefinite-Lived Intangible Assets (Excluding Goodwill), Beginning Balance",
        "terseLabel": "Net carrying amount",
        "totalLabel": "Indefinite-Lived Intangible Assets (Excluding Goodwill), Total"
       }
      }
     },
     "localname": "IndefiniteLivedIntangibleAssetsExcludingGoodwill",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain": {
     "auth_ref": [
      "r96",
      "r101"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The major class of indefinite-lived intangible asset (for example, trade names, etc. but not all-inclusive), excluding goodwill. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of the company.",
        "label": "Indefinite-Lived Intangible Assets, Major Class Name [Domain]",
        "terseLabel": "Indefinite-lived Intangible Assets, Major Class Name"
       }
      }
     },
     "localname": "IndefiniteLivedIntangibleAssetsMajorClassNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_IntangibleAssetsGrossExcludingGoodwill": {
     "auth_ref": [
      "r262"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_IntangibleAssetsNetExcludingGoodwill",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before accumulated amortization of intangible assets, excluding goodwill.",
        "label": "Intangible Assets, Gross (Excluding Goodwill)",
        "terseLabel": "Gross carrying amount",
        "totalLabel": "Intangible Assets, Gross (Excluding Goodwill), Total"
       }
      }
     },
     "localname": "IntangibleAssetsGrossExcludingGoodwill",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IntangibleAssetsNetExcludingGoodwill": {
     "auth_ref": [
      "r92",
      "r97"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 4.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.",
        "label": "Intangible Assets, Net (Excluding Goodwill)",
        "terseLabel": "Other intangible assets, net",
        "totalLabel": "Net carrying amount"
       }
      }
     },
     "localname": "IntangibleAssetsNetExcludingGoodwill",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InterestAndOtherIncome": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).",
        "label": "Interest and Other Income",
        "terseLabel": "Interest income"
       }
      }
     },
     "localname": "InterestAndOtherIncome",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InterestExpense": {
     "auth_ref": [
      "r212",
      "r228",
      "r282",
      "r359",
      "r689"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail": {
       "order": 2.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": -1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 1.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the cost of borrowed funds accounted for as interest expense.",
        "label": "Interest Expense",
        "negatedLabel": "Interest expense",
        "terseLabel": "Interest expense",
        "totalLabel": "Interest Expense, Total"
       }
      }
     },
     "localname": "InterestExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InterestExpenseDebt": {
     "auth_ref": [
      "r50",
      "r468",
      "r476",
      "r795",
      "r796"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of the cost of borrowed funds accounted for as interest expense for debt.",
        "label": "Interest Expense, Debt",
        "totalLabel": "Total"
       }
      }
     },
     "localname": "InterestExpenseDebt",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InterestExpenseDebtExcludingAmortization": {
     "auth_ref": [
      "r52",
      "r469",
      "r795",
      "r796"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_InterestExpenseDebt",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.",
        "label": "Interest Expense, Debt, Excluding Amortization",
        "terseLabel": "Contractual interest expense"
       }
      }
     },
     "localname": "InterestExpenseDebtExcludingAmortization",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureDebtScheduleOfInterestExpenseRelatedTo2027And2024NotesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InterestIncomeAndInterestExpenseDisclosureTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of interest income and expense, including, but not limited to, interest income and expense from investments, loans, and securities.",
        "label": "Interest Income and Interest Expense Disclosure [Table Text Block]",
        "terseLabel": "Schedule of Interest Expense Related to 2027 and 2024 Notes"
       }
      }
     },
     "localname": "InterestIncomeAndInterestExpenseDisclosureTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_InterestOnConvertibleDebtNetOfTax": {
     "auth_ref": [
      "r328",
      "r334",
      "r338"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after tax, of interest recognized on convertible debt instrument excluding interest on principal required to be paid in cash.",
        "label": "Interest on Convertible Debt, Net of Tax",
        "terseLabel": "Interest expense related to Convertible Notes, net of tax"
       }
      }
     },
     "localname": "InterestOnConvertibleDebtNetOfTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InterestPaidNet": {
     "auth_ref": [
      "r288",
      "r291",
      "r292"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.",
        "label": "Interest Paid, Excluding Capitalized Interest, Operating Activities",
        "terseLabel": "Interest paid"
       }
      }
     },
     "localname": "InterestPaidNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InvestmentPolicyTextBlock": {
     "auth_ref": [
      "r393",
      "r954"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for investment in financial asset.",
        "label": "Investment, Policy [Policy Text Block]",
        "terseLabel": "Other Investments"
       }
      }
     },
     "localname": "InvestmentPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_LandMember": {
     "auth_ref": [
      "r898"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Part of earth's surface not covered by water.",
        "label": "Land [Member]",
        "terseLabel": "Land [Member]"
       }
      }
     },
     "localname": "LandMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LeaseCostTableTextBlock": {
     "auth_ref": [
      "r943"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of lessee's lease cost. Includes, but is not limited to, interest expense for finance lease, amortization of right-of-use asset for finance lease, operating lease cost, short-term lease cost, variable lease cost and sublease income.",
        "label": "Lease, Cost [Table Text Block]",
        "terseLabel": "Schedule of Components of Lease Cost"
       }
      }
     },
     "localname": "LeaseCostTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_LeaseholdImprovementsMember": {
     "auth_ref": [
      "r110"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Additions or improvements to assets held under a lease arrangement.",
        "label": "Leasehold Improvements [Member]",
        "terseLabel": "Leasehold Improvements [Member]"
       }
      }
     },
     "localname": "LeaseholdImprovementsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LeasesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Leases [Abstract]"
       }
      }
     },
     "localname": "LeasesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_LesseeLeaseDescriptionLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Lessee, Lease, Description [Line Items]",
        "terseLabel": "Lessee Lease Description [Line Items]"
       }
      }
     },
     "localname": "LesseeLeaseDescriptionLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LesseeLeaseDescriptionTable": {
     "auth_ref": [
      "r705"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of information about lessee's leases.",
        "label": "Lessee, Lease, Description [Table]",
        "terseLabel": "Lessee Lease Description [Table]"
       }
      }
     },
     "localname": "LesseeLeaseDescriptionTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LesseeLeasesPolicyTextBlock": {
     "auth_ref": [
      "r704"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for leasing arrangement entered into by lessee.",
        "label": "Lessee, Leases [Policy Text Block]",
        "terseLabel": "Leases"
       }
      }
     },
     "localname": "LesseeLeasesPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock": {
     "auth_ref": [
      "r944"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of undiscounted cash flows of lessee's operating lease liability. Includes, but is not limited to, reconciliation of undiscounted cash flows to operating lease liability recognized in statement of financial position.",
        "label": "Lessee, Operating Lease, Liability, Maturity [Table Text Block]",
        "terseLabel": "Schedule of Maturities of Operating Lease Liabilities"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityMaturityTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue": {
     "auth_ref": [
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail2": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payment for operating lease.",
        "label": "Lessee, Operating Lease, Liability, to be Paid",
        "totalLabel": "Total lease payments"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive": {
     "auth_ref": [
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail": {
       "order": 5.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Lessee, Operating Lease, Liability, to be Paid, after Year Five",
        "terseLabel": "Thereafter"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths": {
     "auth_ref": [
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Lessee, Operating Lease, Liability, to be Paid, Year One",
        "terseLabel": "2023"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive": {
     "auth_ref": [
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail": {
       "order": 4.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Lessee, Operating Lease, Liability, to be Paid, Year Five",
        "terseLabel": "2027"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearFive",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour": {
     "auth_ref": [
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail": {
       "order": 3.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Lessee, Operating Lease, Liability, to be Paid, Year Four",
        "terseLabel": "2026"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearFour",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree": {
     "auth_ref": [
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Lessee, Operating Lease, Liability, to be Paid, Year Three",
        "terseLabel": "2025"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearThree",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo": {
     "auth_ref": [
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Lessee, Operating Lease, Liability, to be Paid, Year Two",
        "terseLabel": "2024"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearTwo",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount": {
     "auth_ref": [
      "r712"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail2": {
       "order": 0.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.",
        "label": "Lessee, Operating Lease, Liability, Undiscounted Excess Amount",
        "terseLabel": "Less: imputed interest"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityUndiscountedExcessAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseRenewalTerm": {
     "auth_ref": [
      "r942"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Lessee, Operating Lease, Renewal Term",
        "terseLabel": "Operating leases, options to extend lease term"
       }
      }
     },
     "localname": "LesseeOperatingLeaseRenewalTerm",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_Liabilities": {
     "auth_ref": [
      "r18",
      "r296",
      "r394",
      "r439",
      "r440",
      "r441",
      "r442",
      "r443",
      "r444",
      "r445",
      "r446",
      "r447",
      "r638",
      "r641",
      "r642",
      "r659",
      "r789",
      "r889",
      "r945",
      "r946"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 0.0,
       "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.",
        "label": "Liabilities",
        "totalLabel": "TOTAL LIABILITIES"
       }
      }
     },
     "localname": "Liabilities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LiabilitiesAndStockholdersEquity": {
     "auth_ref": [
      "r14",
      "r222",
      "r242",
      "r819",
      "r848",
      "r864",
      "r938"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any.",
        "label": "Liabilities and Equity",
        "totalLabel": "TOTAL LIABILITIES, MEZZANINE EQUITY AND STOCKHOLDERS\u2019 EQUITY"
       }
      }
     },
     "localname": "LiabilitiesAndStockholdersEquity",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LiabilitiesAndStockholdersEquityAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Liabilities and Equity [Abstract]",
        "terseLabel": "LIABILITIES, MEZZANINE EQUITY AND STOCKHOLDERS\u2019 EQUITY"
       }
      }
     },
     "localname": "LiabilitiesAndStockholdersEquityAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LiabilitiesCurrent": {
     "auth_ref": [
      "r20",
      "r258",
      "r296",
      "r394",
      "r439",
      "r440",
      "r441",
      "r442",
      "r443",
      "r444",
      "r445",
      "r446",
      "r447",
      "r638",
      "r641",
      "r642",
      "r659",
      "r819",
      "r889",
      "r945",
      "r946"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 0.0,
       "parentTag": "us-gaap_Liabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer.",
        "label": "Liabilities, Current",
        "totalLabel": "Total current liabilities"
       }
      }
     },
     "localname": "LiabilitiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LiabilitiesCurrentAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Liabilities, Current [Abstract]",
        "terseLabel": "CURRENT LIABILITIES"
       }
      }
     },
     "localname": "LiabilitiesCurrentAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LicenseAndMaintenanceMember": {
     "auth_ref": [
      "r898"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Right to use intangible asset and process of preserving asset. Intangible asset includes, but is not limited to, patent, copyright, technology, manufacturing process, software or trademark.",
        "label": "License and Maintenance [Member]",
        "terseLabel": "Total Software [Member]"
       }
      }
     },
     "localname": "LicenseAndMaintenanceMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LicenseAndServiceMember": {
     "auth_ref": [
      "r898"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Right to use intangible asset and performance of related service. Intangible asset includes, but is not limited to, patent, copyright, technology, manufacturing process, software or trademark.",
        "label": "License and Service [Member]",
        "terseLabel": "Total Software and Related Services [Member]"
       }
      }
     },
     "localname": "LicenseAndServiceMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LicenseMember": {
     "auth_ref": [
      "r898"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Right to use intangible asset. Intangible asset includes, but is not limited to, patent, copyright, technology, manufacturing process, software or trademark.",
        "label": "License [Member]",
        "terseLabel": "License [Member]"
       }
      }
     },
     "localname": "LicenseMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LineOfCredit": {
     "auth_ref": [
      "r3",
      "r221",
      "r235"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.",
        "label": "Long-Term Line of Credit",
        "terseLabel": "Loan outstanding",
        "totalLabel": "Long-Term Line of Credit, Total"
       }
      }
     },
     "localname": "LineOfCredit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity": {
     "auth_ref": [
      "r16"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.",
        "label": "Line of Credit Facility, Current Borrowing Capacity",
        "terseLabel": "Credit facility"
       }
      }
     },
     "localname": "LineOfCreditFacilityCurrentBorrowingCapacity",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LineOfCreditFacilityExpirationDate1": {
     "auth_ref": [
      "r16"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Date the credit facility terminates, in YYYY-MM-DD format.",
        "label": "Line of Credit Facility, Expiration Date",
        "terseLabel": "Maturity date"
       }
      }
     },
     "localname": "LineOfCreditFacilityExpirationDate1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "dateItemType"
    },
    "us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd": {
     "auth_ref": [
      "r16"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The effective interest rate at the end of the reporting period.",
        "label": "Line of Credit Facility, Interest Rate at Period End",
        "terseLabel": "Weighted Average Interest Rate on borrowings"
       }
      }
     },
     "localname": "LineOfCreditFacilityInterestRateAtPeriodEnd",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity": {
     "auth_ref": [
      "r16"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.",
        "label": "Line of Credit Facility, Maximum Borrowing Capacity",
        "terseLabel": "Amount available under secured credit agreement"
       }
      }
     },
     "localname": "LineOfCreditFacilityMaximumBorrowingCapacity",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity": {
     "auth_ref": [
      "r16"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).",
        "label": "Line of Credit Facility, Remaining Borrowing Capacity",
        "terseLabel": "Amount available for future borrowing"
       }
      }
     },
     "localname": "LineOfCreditFacilityRemainingBorrowingCapacity",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.",
        "label": "Line of Credit Facility, Unused Capacity, Commitment Fee Percentage",
        "terseLabel": "Commitment fees on unused portion of the Revolving Credit Facility"
       }
      }
     },
     "localname": "LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_LondonInterbankOfferedRateLIBORMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Interest rate at which a bank borrows funds from other banks in the London interbank market.",
        "label": "London Interbank Offered Rate (LIBOR) [Member]",
        "terseLabel": "London Interbank Offered Rate (LIBOR) [Member]"
       }
      }
     },
     "localname": "LondonInterbankOfferedRateLIBORMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LongTermDebtPercentageBearingVariableInterestRate": {
     "auth_ref": [
      "r21"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.",
        "label": "Long-Term Debt, Percentage Bearing Variable Interest, Percentage Rate",
        "terseLabel": "Applicable margin for borrowings under new credit facility"
       }
      }
     },
     "localname": "LongTermDebtPercentageBearingVariableInterestRate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_LongtermDebtTypeAxis": {
     "auth_ref": [
      "r23"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of long-term debt.",
        "label": "Long-Term Debt, Type [Axis]",
        "terseLabel": "Long-term Debt, Type"
       }
      }
     },
     "localname": "LongtermDebtTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LongtermDebtTypeDomain": {
     "auth_ref": [
      "r23",
      "r121"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Type of long-term debt arrangement, such as notes, line of credit, commercial paper, asset-based financing, project financing, letter of credit financing. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the company, if longer.",
        "label": "Long-Term Debt, Type [Domain]",
        "terseLabel": "Long-term Debt, Type"
       }
      }
     },
     "localname": "LongtermDebtTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LossContingenciesLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Loss Contingencies [Line Items]",
        "terseLabel": "Loss Contingencies [Line Items]"
       }
      }
     },
     "localname": "LossContingenciesLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LossContingenciesTable": {
     "auth_ref": [
      "r118",
      "r119",
      "r434",
      "r435",
      "r436",
      "r883",
      "r884"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Discloses the specific components (such as the nature, name, and date) of the loss contingency and gives an estimate of the possible loss or range of loss, or states that a reasonable estimate cannot be made. Excludes environmental contingencies, warranties and unconditional purchase obligations.",
        "label": "Loss Contingencies [Table]",
        "terseLabel": "Loss Contingencies [Table]"
       }
      }
     },
     "localname": "LossContingenciesTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LossContingencyDamagesAwardedValue": {
     "auth_ref": [
      "r882",
      "r883",
      "r884"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of damages awarded to the plaintiff in the legal matter.",
        "label": "Loss Contingency, Damages Awarded, Value",
        "terseLabel": "Loss contingency damages awarded value"
       }
      }
     },
     "localname": "LossContingencyDamagesAwardedValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LossContingencyDamagesPaidValue": {
     "auth_ref": [
      "r882",
      "r883",
      "r884"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of damages paid to the plaintiff in the legal matter.",
        "label": "Loss Contingency, Damages Paid, Value",
        "terseLabel": "Outstanding loss contingency damages paid"
       }
      }
     },
     "localname": "LossContingencyDamagesPaidValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_MaintenanceMember": {
     "auth_ref": [
      "r898"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Process of preserving asset, including, but not limited to, building, machinery and software.",
        "label": "Maintenance [Member]",
        "terseLabel": "Maintenance [Member]"
       }
      }
     },
     "localname": "MaintenanceMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_MinistryOfTheEconomyFinanceAndIndustryFranceMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Designated tax department of the government of France.",
        "label": "Ministry of the Economy, Finance and Industry, France [Member]",
        "terseLabel": "Ministry of the Economy, Finance and Industry, France [Member]"
       }
      }
     },
     "localname": "MinistryOfTheEconomyFinanceAndIndustryFranceMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_NatureOfOperations": {
     "auth_ref": [
      "r347",
      "r352"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.",
        "label": "Nature of Operations [Text Block]",
        "terseLabel": "Description of Business"
       }
      }
     },
     "localname": "NatureOfOperations",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDescriptionOfBusiness"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_NetCashProvidedByUsedInFinancingActivities": {
     "auth_ref": [
      "r290"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 2.0,
       "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.",
        "label": "Net Cash Provided by (Used in) Financing Activities",
        "totalLabel": "Net cash provided by financing activities"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInFinancingActivities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Net Cash Provided by (Used in) Financing Activities [Abstract]",
        "terseLabel": "FINANCING ACTIVITIES:"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInFinancingActivitiesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NetCashProvidedByUsedInInvestingActivities": {
     "auth_ref": [
      "r290"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 1.0,
       "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.",
        "label": "Net Cash Provided by (Used in) Investing Activities",
        "totalLabel": "Net cash used in investing activities"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInInvestingActivities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Net Cash Provided by (Used in) Investing Activities [Abstract]",
        "terseLabel": "INVESTING ACTIVITIES:"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInInvestingActivitiesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NetCashProvidedByUsedInOperatingActivities": {
     "auth_ref": [
      "r61",
      "r63",
      "r66"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 0.0,
       "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect",
       "weight": 1.0
      }
     },
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.",
        "label": "Net Cash Provided by (Used in) Operating Activities",
        "totalLabel": "Net cash provided by operating activities"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInOperatingActivities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Net Cash Provided by (Used in) Operating Activities [Abstract]",
        "terseLabel": "OPERATING ACTIVITIES:"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInOperatingActivitiesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NetIncomeLoss": {
     "auth_ref": [
      "r42",
      "r66",
      "r227",
      "r247",
      "r256",
      "r273",
      "r276",
      "r281",
      "r296",
      "r313",
      "r317",
      "r318",
      "r319",
      "r320",
      "r323",
      "r324",
      "r335",
      "r365",
      "r370",
      "r376",
      "r379",
      "r394",
      "r439",
      "r440",
      "r441",
      "r442",
      "r443",
      "r444",
      "r445",
      "r446",
      "r447",
      "r655",
      "r659",
      "r790",
      "r889"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome": {
       "order": 0.0,
       "parentTag": "us-gaap_ComprehensiveIncomeNetOfTax",
       "weight": 1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.",
        "label": "Net Income (Loss) Attributable to Parent",
        "terseLabel": "Net loss",
        "totalLabel": "Net loss"
       }
      }
     },
     "localname": "NetIncomeLoss",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NetIncomeLossAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Net Income (Loss) Attributable to Parent [Abstract]",
        "terseLabel": "Numerator:"
       }
      }
     },
     "localname": "NetIncomeLossAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NetIncomeLossAttributableToParentDiluted": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The portion of profit or loss for the period, net of income taxes, which is attributable to the parent, and includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.",
        "label": "Net Income (Loss) Attributable to Parent, Diluted",
        "terseLabel": "Numerator for diluted loss per share",
        "totalLabel": "Net Income (Loss) Attributable to Parent, Diluted, Total"
       }
      }
     },
     "localname": "NetIncomeLossAttributableToParentDiluted",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact.",
        "label": "New Accounting Pronouncements, Policy [Policy Text Block]",
        "terseLabel": "Recent accounting guidance"
       }
      }
     },
     "localname": "NewAccountingPronouncementsPolicyPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_NoncashInvestingAndFinancingItemsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Noncash Investing and Financing Items [Abstract]",
        "terseLabel": "Supplemental disclosure of non-cash investing and financing activities:"
       }
      }
     },
     "localname": "NoncashInvestingAndFinancingItemsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NonoperatingIncomeExpense": {
     "auth_ref": [
      "r49"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 2.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).",
        "label": "Nonoperating Income (Expense)",
        "negatedLabel": "Other expense (income), net",
        "negatedTotalLabel": "Other expense (income), net",
        "totalLabel": "Nonoperating Income (Expense), Total"
       }
      }
     },
     "localname": "NonoperatingIncomeExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NumberOfBusinessesAcquired": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of businesses acquired by the entity during the period.",
        "label": "Number of Businesses Acquired",
        "terseLabel": "Number of business acquisitions completed"
       }
      }
     },
     "localname": "NumberOfBusinessesAcquired",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "us-gaap_NumberOfReportableSegments": {
     "auth_ref": [
      "r863"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.",
        "label": "Number of Reportable Segments",
        "terseLabel": "Number of reportable segments"
       }
      }
     },
     "localname": "NumberOfReportableSegments",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "integerItemType"
    },
    "us-gaap_OperatingExpenses": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 1.0,
       "parentTag": "us-gaap_OperatingIncomeLoss",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.",
        "label": "Operating Expenses",
        "totalLabel": "Total operating expenses"
       }
      }
     },
     "localname": "OperatingExpenses",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingExpensesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Operating Expenses [Abstract]",
        "terseLabel": "Operating expenses"
       }
      }
     },
     "localname": "OperatingExpensesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OperatingIncomeLoss": {
     "auth_ref": [
      "r365",
      "r370",
      "r376",
      "r379",
      "r790"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 0.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The net result for the period of deducting operating expenses from operating revenues.",
        "label": "Operating Income (Loss)",
        "totalLabel": "Operating (loss) income"
       }
      }
     },
     "localname": "OperatingIncomeLoss",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingIncomeLossMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Primary financial statement caption encompassing operating income (loss).",
        "label": "Operating Income (Loss) [Member]",
        "terseLabel": "Operating Income [Member]"
       }
      }
     },
     "localname": "OperatingIncomeLossMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_OperatingLeaseCost": {
     "auth_ref": [
      "r707",
      "r818"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.",
        "label": "Operating Lease, Cost",
        "terseLabel": "Operating lease cost"
       }
      }
     },
     "localname": "OperatingLeaseCost",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfComponentsOfLeaseCostDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseExpense": {
     "auth_ref": [
      "r941"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of operating lease expense. Excludes sublease income.",
        "label": "Operating Lease, Expense",
        "terseLabel": "Rent cost for operating leases"
       }
      }
     },
     "localname": "OperatingLeaseExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseLiability": {
     "auth_ref": [
      "r698"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail2": {
       "order": 1.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Present value of lessee's discounted obligation for lease payments from operating lease.",
        "label": "Operating Lease, Liability",
        "totalLabel": "Total operating lease liabilities",
        "verboseLabel": "Total operating lease liabilities"
       }
      }
     },
     "localname": "OperatingLeaseLiability",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfMaturitiesOfOperatingLeaseLiabilitiesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseLiabilityCurrent": {
     "auth_ref": [
      "r698"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_OperatingLeaseLiability",
       "weight": 1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_LiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.",
        "label": "Operating Lease, Liability, Current",
        "terseLabel": "Current portion of operating lease liabilities"
       }
      }
     },
     "localname": "OperatingLeaseLiabilityCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseLiabilityNoncurrent": {
     "auth_ref": [
      "r698"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_OperatingLeaseLiability",
       "weight": 1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_Liabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.",
        "label": "Operating Lease, Liability, Noncurrent",
        "terseLabel": "Operating lease liabilities, net of current portion"
       }
      }
     },
     "localname": "OperatingLeaseLiabilityNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeasePayments": {
     "auth_ref": [
      "r703",
      "r708"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.",
        "label": "Operating Lease, Payments",
        "negatedLabel": "Operating cash flows from operating leases"
       }
      }
     },
     "localname": "OperatingLeasePayments",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalCashFlowInformationRelatedToLeasesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseRightOfUseAsset": {
     "auth_ref": [
      "r697"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of lessee's right to use underlying asset under operating lease.",
        "label": "Operating Lease, Right-of-Use Asset",
        "terseLabel": "Operating lease right of use assets"
       }
      }
     },
     "localname": "OperatingLeaseRightOfUseAsset",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent": {
     "auth_ref": [
      "r711",
      "r818"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average discount rate for operating lease calculated at point in time.",
        "label": "Operating Lease, Weighted Average Discount Rate, Percent",
        "terseLabel": "Weighted average discount rate"
       }
      }
     },
     "localname": "OperatingLeaseWeightedAverageDiscountRatePercent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1": {
     "auth_ref": [
      "r710",
      "r818"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Operating Lease, Weighted Average Remaining Lease Term",
        "terseLabel": "Weighted average remaining lease term"
       }
      }
     },
     "localname": "OperatingLeaseWeightedAverageRemainingLeaseTerm1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalBalanceSheetInformationRelatedToLeaseLiabilitiesDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_OptionIndexedToIssuersEquityTypeAxis": {
     "auth_ref": [
      "r127",
      "r199",
      "r200",
      "r201"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of freestanding contracts issued by an entity that are indexed to, and potentially settled in, an entity's own stock.",
        "label": "Option Indexed to Issuer's Equity, Type [Axis]",
        "terseLabel": "Option Indexed to Issuer's Equity, Type"
       }
      }
     },
     "localname": "OptionIndexedToIssuersEquityTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OptionIndexedToIssuersEquityTypeDomain": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Description of the type of freestanding contract issued by a Company that is indexed to, and potentially settled in, a Company's own stock. Specifically, the pertinent rights and privileges of the securities outstanding.",
        "label": "Option Indexed to Issuer's Equity, Type [Domain]",
        "terseLabel": "Option Indexed to Issuer's Equity, Type"
       }
      }
     },
     "localname": "OptionIndexedToIssuersEquityTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Organization, Consolidation and Presentation of Financial Statements [Abstract]"
       }
      }
     },
     "localname": "OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_OtherAssetsNoncurrent": {
     "auth_ref": [
      "r264"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 6.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of noncurrent assets classified as other.",
        "label": "Other Assets, Noncurrent",
        "terseLabel": "Other long-term assets"
       }
      }
     },
     "localname": "OtherAssetsNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax": {
     "auth_ref": [
      "r37",
      "r280",
      "r675",
      "r677",
      "r682",
      "r837"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_OtherComprehensiveIncomeLossNetOfTax",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before tax and reclassification adjustments of other comprehensive income (loss).",
        "label": "Other Comprehensive Income (Loss), before Reclassifications, before Tax",
        "terseLabel": "Other comprehensive income (loss) before reclassification"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax": {
     "auth_ref": [
      "r29"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome": {
       "order": 0.0,
       "parentTag": "us-gaap_OtherComprehensiveIncomeLossNetOfTax",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.",
        "label": "Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax",
        "terseLabel": "Foreign currency translation (net of tax effect of $0 for all periods)",
        "totalLabel": "Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total",
        "verboseLabel": "Foreign currency translation, net of tax"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax": {
     "auth_ref": [
      "r29",
      "r35",
      "r672",
      "r681"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.",
        "label": "Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax",
        "terseLabel": "Foreign currency translation, tax effect",
        "totalLabel": "Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax, Total"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncomeParenthetical"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossNetOfTax": {
     "auth_ref": [
      "r39",
      "r133",
      "r274",
      "r277",
      "r283",
      "r675",
      "r680",
      "r682",
      "r733",
      "r739",
      "r837",
      "r838"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome": {
       "order": 1.0,
       "parentTag": "us-gaap_ComprehensiveIncomeNetOfTax",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount after tax and reclassification adjustments of other comprehensive income (loss).",
        "label": "Other Comprehensive Income (Loss), Net of Tax",
        "totalLabel": "Total other comprehensive (loss) income"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossNetOfTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Comprehensive Income (Loss), Net of Tax [Abstract]",
        "terseLabel": "Other comprehensive (loss) income, net of tax:"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax": {
     "auth_ref": [
      "r32",
      "r34"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome": {
       "order": 1.0,
       "parentTag": "us-gaap_OtherComprehensiveIncomeLossNetOfTax",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.",
        "label": "Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax",
        "negatedLabel": "Retirement related benefit plans (net of tax effect of $(308), $(296) and $308, respectively)",
        "negatedTerseLabel": "Retirement related benefit plans, net of tax",
        "totalLabel": "Retirement related benefit plans (net of tax effect of $(40), $(296) and $308, respectively"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax": {
     "auth_ref": [
      "r32",
      "r35",
      "r190"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.",
        "label": "Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax",
        "terseLabel": "Retirement related benefit plans, tax effect",
        "totalLabel": "Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax, Total"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncomeParenthetical"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossTax": {
     "auth_ref": [
      "r35",
      "r279",
      "r283",
      "r593",
      "r623",
      "r625",
      "r675",
      "r678",
      "r682",
      "r733",
      "r739"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_OtherComprehensiveIncomeLossNetOfTax",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of tax expense (benefit) allocated to other comprehensive income (loss).",
        "label": "Other Comprehensive Income (Loss), Tax",
        "negatedLabel": "Tax effects",
        "totalLabel": "Other Comprehensive Income (Loss), Tax, Total"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherCurrentLiabilitiesTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of other current liabilities.",
        "label": "Other Current Liabilities [Table Text Block]",
        "terseLabel": "Summary of Other Accrued Expenses and Current Liabilities"
       }
      }
     },
     "localname": "OtherCurrentLiabilitiesTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_OtherIntangibleAssetsMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Intangible assets classified as other.",
        "label": "Other Intangible Assets [Member]",
        "terseLabel": "Other Intangibles [Member]"
       }
      }
     },
     "localname": "OtherIntangibleAssetsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_OtherLiabilitiesCurrent": {
     "auth_ref": [
      "r19",
      "r819"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 4.0,
       "parentTag": "us-gaap_LiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.",
        "label": "Other Liabilities, Current",
        "terseLabel": "Other accrued expenses and current liabilities",
        "totalLabel": "Total"
       }
      }
     },
     "localname": "OtherLiabilitiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherLiabilitiesDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Other Liabilities Disclosure [Abstract]"
       }
      }
     },
     "localname": "OtherLiabilitiesDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_OtherLiabilitiesNoncurrent": {
     "auth_ref": [
      "r24"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 4.0,
       "parentTag": "us-gaap_Liabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.",
        "label": "Other Liabilities, Noncurrent",
        "terseLabel": "Other long-term liabilities",
        "totalLabel": "Total"
       }
      }
     },
     "localname": "OtherLiabilitiesNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherNoncashIncomeExpense": {
     "auth_ref": [
      "r66"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 7.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of income (expense) included in net income that results in no cash inflow (outflow), classified as other.",
        "label": "Other Noncash Income (Expense)",
        "negatedLabel": "Other, net",
        "totalLabel": "Other Noncash Income (Expense), Total"
       }
      }
     },
     "localname": "OtherNoncashIncomeExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherNoncurrentAssetsMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Primary financial statement caption encompassing other noncurrent assets.",
        "label": "Other Noncurrent Assets [Member]",
        "terseLabel": "Other Long-Term Assets [Member]"
       }
      }
     },
     "localname": "OtherNoncurrentAssetsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_OtherNoncurrentLiabilitiesTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of other noncurrent liabilities.",
        "label": "Other Noncurrent Liabilities [Table Text Block]",
        "terseLabel": "Summary of Other Long-term Liabilities"
       }
      }
     },
     "localname": "OtherNoncurrentLiabilitiesTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_OtherNonoperatingIncomeExpense": {
     "auth_ref": [
      "r51"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_NonoperatingIncomeExpense",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of income (expense) related to nonoperating activities, classified as other.",
        "label": "Other Nonoperating Income (Expense)",
        "negatedLabel": "Other income, net",
        "negatedTotalLabel": "Other income, net",
        "terseLabel": "Other expense (income), net",
        "totalLabel": "Other Nonoperating Income (Expense), Total"
       }
      }
     },
     "localname": "OtherNonoperatingIncomeExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfOtherExpenseIncomeNetDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherOperatingIncomeExpenseNet": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 4.0,
       "parentTag": "us-gaap_OperatingExpenses",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.",
        "label": "Other Operating Income (Expense), Net",
        "negatedLabel": "Other operating income, net"
       }
      }
     },
     "localname": "OtherOperatingIncomeExpenseNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherSundryLiabilitiesCurrent": {
     "auth_ref": [
      "r19",
      "r120"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 10.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are due within one year or operating cycle, if longer, from the balance sheet date.",
        "label": "Other Sundry Liabilities, Current",
        "terseLabel": "Other current liabilities"
       }
      }
     },
     "localname": "OtherSundryLiabilitiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherSundryLiabilitiesNoncurrent": {
     "auth_ref": [
      "r4",
      "r220",
      "r239"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail": {
       "order": 2.0,
       "parentTag": "us-gaap_OtherLiabilitiesNoncurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.",
        "label": "Other Sundry Liabilities, Noncurrent",
        "terseLabel": "Other liabilities"
       }
      }
     },
     "localname": "OtherSundryLiabilitiesNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsForProceedsFromOtherInvestingActivities": {
     "auth_ref": [
      "r840",
      "r841"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 3.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash (inflow) outflow from investing activities classified as other.",
        "label": "Payments for (Proceeds from) Other Investing Activities",
        "negatedLabel": "Other investing activities, net"
       }
      }
     },
     "localname": "PaymentsForProceedsFromOtherInvestingActivities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsForRepurchaseOfCommonStock": {
     "auth_ref": [
      "r58"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 2.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash outflow to reacquire common stock during the period.",
        "label": "Payments for Repurchase of Common Stock",
        "negatedLabel": "Repurchase and retirement of common stock"
       }
      }
     },
     "localname": "PaymentsForRepurchaseOfCommonStock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsOfDebtIssuanceCosts": {
     "auth_ref": [
      "r60"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 5.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.",
        "label": "Payments of Debt Issuance Costs",
        "negatedLabel": "Payments for issuance costs of convertible senior notes"
       }
      }
     },
     "localname": "PaymentsOfDebtIssuanceCosts",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsToAcquireBusinessesGross": {
     "auth_ref": [
      "r54",
      "r634"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.",
        "label": "Payments to Acquire Businesses, Gross",
        "terseLabel": "Amount of cash consideration"
       }
      }
     },
     "localname": "PaymentsToAcquireBusinessesGross",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired": {
     "auth_ref": [
      "r54"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 0.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.",
        "label": "Payments to Acquire Businesses, Net of Cash Acquired",
        "negatedLabel": "Payments for acquisition of businesses, net of cash acquired",
        "totalLabel": "Payments to Acquire Businesses, Net of Cash Acquired, Total"
       }
      }
     },
     "localname": "PaymentsToAcquireBusinessesNetOfCashAcquired",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsToAcquirePropertyPlantAndEquipment": {
     "auth_ref": [
      "r55"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 1.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.",
        "label": "Payments to Acquire Property, Plant, and Equipment",
        "negatedLabel": "Capital expenditures",
        "totalLabel": "Payments to Acquire Property, Plant, and Equipment, Total"
       }
      }
     },
     "localname": "PaymentsToAcquirePropertyPlantAndEquipment",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesNoncurrent": {
     "auth_ref": [
      "r4",
      "r142",
      "r143",
      "r144"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_OtherLiabilitiesNoncurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of liability, recognized in statement of financial position, for pension, other postretirement and postemployment benefits, classified as noncurrent.",
        "label": "Liability, Pension and Other Postretirement and Postemployment Benefits, Noncurrent",
        "terseLabel": "Pension and other post retirement liabilities",
        "totalLabel": "Liability, Pension and Other Postretirement and Postemployment Benefits, Noncurrent, Total"
       }
      }
     },
     "localname": "PensionAndOtherPostretirementAndPostemploymentBenefitPlansLiabilitiesNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherLongTermLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock": {
     "auth_ref": [
      "r523",
      "r524",
      "r525",
      "r529",
      "r530",
      "r531",
      "r532",
      "r533",
      "r534",
      "r536",
      "r537",
      "r539",
      "r541",
      "r806"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for retirement benefits.",
        "label": "Retirement Benefits [Text Block]",
        "terseLabel": "Retirement Benefits"
       }
      }
     },
     "localname": "PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefits"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_PlanNameAxis": {
     "auth_ref": [
      "r899",
      "r900",
      "r901",
      "r902",
      "r903",
      "r904",
      "r905",
      "r906",
      "r907",
      "r908",
      "r909",
      "r910",
      "r911",
      "r912",
      "r913",
      "r914",
      "r915",
      "r916",
      "r917",
      "r918",
      "r919",
      "r920",
      "r921",
      "r922",
      "r923",
      "r924"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by plan name for share-based payment arrangement.",
        "label": "Plan Name [Axis]",
        "terseLabel": "Plan Name"
       }
      }
     },
     "localname": "PlanNameAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_PlanNameDomain": {
     "auth_ref": [
      "r899",
      "r900",
      "r901",
      "r902",
      "r903",
      "r904",
      "r905",
      "r906",
      "r907",
      "r908",
      "r909",
      "r910",
      "r911",
      "r912",
      "r913",
      "r914",
      "r915",
      "r916",
      "r917",
      "r918",
      "r919",
      "r920",
      "r921",
      "r922",
      "r923",
      "r924"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Plan name for share-based payment arrangement.",
        "label": "Plan Name [Domain]",
        "terseLabel": "Plan Name"
       }
      }
     },
     "localname": "PlanNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_PreferredStockParOrStatedValuePerShare": {
     "auth_ref": [
      "r8",
      "r477"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.",
        "label": "Preferred Stock, Par or Stated Value Per Share",
        "terseLabel": "Preferred stock, par value"
       }
      }
     },
     "localname": "PreferredStockParOrStatedValuePerShare",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_PreferredStockSharesAuthorized": {
     "auth_ref": [
      "r8"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.",
        "label": "Preferred Stock, Shares Authorized",
        "terseLabel": "Preferred stock, shares authorized"
       }
      }
     },
     "localname": "PreferredStockSharesAuthorized",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_PreferredStockSharesIssued": {
     "auth_ref": [
      "r8",
      "r477"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.",
        "label": "Preferred Stock, Shares Issued",
        "terseLabel": "Preferred stock, shares issued"
       }
      }
     },
     "localname": "PreferredStockSharesIssued",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_PreferredStockSharesOutstanding": {
     "auth_ref": [
      "r8"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.",
        "label": "Preferred Stock, Shares Outstanding",
        "periodEndLabel": "Preferred Stock, Shares Outstanding, Ending Balance",
        "periodStartLabel": "Preferred Stock, Shares Outstanding, Beginning Balance",
        "terseLabel": "Preferred stock, shares outstanding"
       }
      }
     },
     "localname": "PreferredStockSharesOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_PreferredStockValue": {
     "auth_ref": [
      "r8",
      "r819"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 0.0,
       "parentTag": "us-gaap_StockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity.",
        "label": "Preferred Stock, Value, Issued",
        "terseLabel": "Preferred stock ($0.0001 par value), authorized 45,000 shares, none issued or outstanding"
       }
      }
     },
     "localname": "PreferredStockValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PrepaidExpenseAndOtherAssetsCurrent": {
     "auth_ref": [
      "r836"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_AssetsCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.",
        "label": "Prepaid Expense and Other Assets, Current",
        "terseLabel": "Prepaid expenses and other current assets"
       }
      }
     },
     "localname": "PrepaidExpenseAndOtherAssetsCurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Primary financial statement caption encompassing prepaid expenses and other current assets.",
        "label": "Prepaid Expenses and Other Current Assets [Member]",
        "terseLabel": "Prepaid and Other Current Assets [Member]"
       }
      }
     },
     "localname": "PrepaidExpensesAndOtherCurrentAssetsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_PrivatePlacementMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A private placement is a direct offering of securities to a limited number of sophisticated investors such as insurance companies, pension funds, mezzanine funds, stock funds and trusts.",
        "label": "Private Placement [Member]",
        "terseLabel": "Private Placement [Member]"
       }
      }
     },
     "localname": "PrivatePlacementMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ProceedsFromConvertibleDebt": {
     "auth_ref": [
      "r57"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 0.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.",
        "label": "Proceeds from Convertible Debt",
        "terseLabel": "Proceeds from issuance of convertible senior notes, net of underwriters' discounts and commissions"
       }
      }
     },
     "localname": "ProceedsFromConvertibleDebt",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromDebtNetOfIssuanceCosts": {
     "auth_ref": [
      "r287"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.",
        "label": "Proceeds from Debt, Net of Issuance Costs",
        "terseLabel": "Net proceeds from issuance of costs"
       }
      }
     },
     "localname": "ProceedsFromDebtNetOfIssuanceCosts",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromIssuanceOfPrivatePlacement": {
     "auth_ref": [
      "r56"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 6.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.",
        "label": "Proceeds from Issuance of Private Placement",
        "terseLabel": "Proceeds from private placement of common stock"
       }
      }
     },
     "localname": "ProceedsFromIssuanceOfPrivatePlacement",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromLongTermLinesOfCredit": {
     "auth_ref": [
      "r57"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 9.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.",
        "label": "Proceeds from Long-Term Lines of Credit",
        "terseLabel": "Borrowings under revolving commitment"
       }
      }
     },
     "localname": "ProceedsFromLongTermLinesOfCredit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromPaymentsForOtherFinancingActivities": {
     "auth_ref": [
      "r842",
      "r843"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 10.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash inflow (outflow) from financing activities classified as other.",
        "label": "Proceeds from (Payments for) Other Financing Activities",
        "terseLabel": "Other financing activities"
       }
      }
     },
     "localname": "ProceedsFromPaymentsForOtherFinancingActivities",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromStockOptionsExercised": {
     "auth_ref": [
      "r56",
      "r153"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 4.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash inflow from exercise of option under share-based payment arrangement.",
        "label": "Proceeds from Stock Options Exercised",
        "terseLabel": "Proceeds from the exercise of common stock options"
       }
      }
     },
     "localname": "ProceedsFromStockOptionsExercised",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProductConcentrationRiskMember": {
     "auth_ref": [
      "r77"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Reflects the percentage that revenues during the period from a specified product are to a specified benchmark, such as total net revenues, segment revenues or product line revenues. May also reflect the percentage contribution the product made to operating results. Risk is materially adverse effects of a loss of sales of a significant product or line of products, which could occur upon loss of rights to sell, distribute or license others; loss of patent or copyright protection; or technological obsolescence.",
        "label": "Product Concentration Risk [Member]",
        "terseLabel": "Product Concentration Risk [Member]"
       }
      }
     },
     "localname": "ProductConcentrationRiskMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ProfitLoss": {
     "auth_ref": [
      "r256",
      "r273",
      "r276",
      "r289",
      "r296",
      "r313",
      "r323",
      "r324",
      "r365",
      "r370",
      "r376",
      "r379",
      "r394",
      "r439",
      "r440",
      "r441",
      "r442",
      "r443",
      "r444",
      "r445",
      "r446",
      "r447",
      "r636",
      "r639",
      "r640",
      "r655",
      "r659",
      "r736",
      "r790",
      "r815",
      "r816",
      "r839",
      "r889"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 0.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.",
        "label": "Net Income (Loss), Including Portion Attributable to Noncontrolling Interest",
        "terseLabel": "Net loss",
        "totalLabel": "Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total"
       }
      }
     },
     "localname": "ProfitLoss",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Property, Plant and Equipment [Abstract]"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentByTypeAxis": {
     "auth_ref": [
      "r112"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of long-lived, physical assets used to produce goods and services and not intended for resale.",
        "label": "Long-Lived Tangible Asset [Axis]",
        "terseLabel": "Long-Lived Tangible Asset"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentByTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentEstimatedUsefulLives": {
     "auth_ref": [
      "r107"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).",
        "label": "Property, Plant and Equipment, Estimated Useful Lives",
        "terseLabel": "Property, Plant and Equipment, Estimated Useful Lives"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentEstimatedUsefulLives",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentGross": {
     "auth_ref": [
      "r110",
      "r260"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_PropertyPlantAndEquipmentNet",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.",
        "label": "Property, Plant and Equipment, Gross",
        "periodEndLabel": "Property, Plant and Equipment, Gross, Ending Balance",
        "periodStartLabel": "Property, Plant and Equipment, Gross, Beginning Balance",
        "terseLabel": "Total property and equipment",
        "totalLabel": "Property, Plant and Equipment, Gross, Total"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentGross",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Property, Plant and Equipment [Line Items]",
        "terseLabel": "Property, Plant and Equipment [Line Items]"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentNet": {
     "auth_ref": [
      "r112",
      "r243",
      "r737",
      "r819"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 1.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.",
        "label": "Property, Plant and Equipment, Net",
        "terseLabel": "Property and equipment, net",
        "totalLabel": "Property and equipment, net"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentNet",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentPolicyTextBlock": {
     "auth_ref": [
      "r112",
      "r768",
      "r769"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for long-lived, physical asset used in normal conduct of business and not intended for resale. Includes, but is not limited to, work of art, historical treasure, and similar asset classified as collections.",
        "label": "Property, Plant and Equipment, Policy [Policy Text Block]",
        "terseLabel": "Property and equipment, net"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentTextBlock": {
     "auth_ref": [
      "r112"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.",
        "label": "Property, Plant and Equipment [Table Text Block]",
        "terseLabel": "Summary of Property and Equipment"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentTypeDomain": {
     "auth_ref": [
      "r110"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Listing of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.",
        "label": "Long-Lived Tangible Asset [Domain]",
        "terseLabel": "Long-Lived Tangible Asset"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentUsefulLife": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.",
        "label": "Property, Plant and Equipment, Useful Life",
        "terseLabel": "Property and equipment, estimated useful life"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentUsefulLife",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_ProvisionForDoubtfulAccounts": {
     "auth_ref": [
      "r286",
      "r406"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of expense (reversal of expense) for expected credit loss on accounts receivable.",
        "label": "Accounts Receivable, Credit Loss Expense (Reversal)",
        "negatedLabel": "Provision charged to expense",
        "terseLabel": "Provision for credit loss"
       }
      }
     },
     "localname": "ProvisionForDoubtfulAccounts",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligation": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.",
        "label": "Purchase Obligation",
        "totalLabel": "Total"
       }
      }
     },
     "localname": "PurchaseObligation",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueAfterFifthYear": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails": {
       "order": 5.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Purchase Obligation, to be Paid, after Year Five",
        "terseLabel": "Thereafter"
       }
      }
     },
     "localname": "PurchaseObligationDueAfterFifthYear",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInFifthYear": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails": {
       "order": 4.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Purchase Obligation, to be Paid, Year Five",
        "terseLabel": "2027"
       }
      }
     },
     "localname": "PurchaseObligationDueInFifthYear",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInFourthYear": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails": {
       "order": 3.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Purchase Obligation, to be Paid, Year Four",
        "terseLabel": "2026"
       }
      }
     },
     "localname": "PurchaseObligationDueInFourthYear",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInNextTwelveMonths": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails": {
       "order": 0.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Purchase Obligation, to be Paid, Year One",
        "terseLabel": "2023"
       }
      }
     },
     "localname": "PurchaseObligationDueInNextTwelveMonths",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInSecondYear": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Purchase Obligation, to be Paid, Year Two",
        "terseLabel": "2024"
       }
      }
     },
     "localname": "PurchaseObligationDueInSecondYear",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInThirdYear": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).",
        "label": "Purchase Obligation, to be Paid, Year Three",
        "terseLabel": "2025"
       }
      }
     },
     "localname": "PurchaseObligationDueInThirdYear",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesFuturePurchaseObligationsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PutOptionMember": {
     "auth_ref": [
      "r757",
      "r758",
      "r759",
      "r760",
      "r761",
      "r762"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A financial contract between two parties, the buyer and the seller (writer) of the option, where the buyer has the right but not the obligation to sell a commodity or financial instrument (the underlying instrument) to the seller (writer) at a certain time for a certain price (the strike price). The seller (writer) has the obligation to purchase the underlying asset at that strike price, if the buyer exercises the option.",
        "label": "Put Option [Member]",
        "terseLabel": "Put Option [Member]"
       }
      }
     },
     "localname": "PutOptionMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax": {
     "auth_ref": [
      "r37",
      "r280",
      "r675",
      "r679",
      "r682",
      "r837"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_OtherComprehensiveIncomeLossNetOfTax",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount before tax of reclassification adjustments of other comprehensive income (loss).",
        "label": "Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax",
        "negatedLabel": "Amounts reclassified from accumulated other comprehensive loss"
       }
      }
     },
     "localname": "ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ReclassificationsOfTemporaryToPermanentEquity": {
     "auth_ref": [
      "r130",
      "r199"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The difference between the carrying amount of a financial instrument subject to a registration payment arrangement recorded as temporary equity prior to adoption of FSP EITF 00-19-2 and the carrying amount reclassified to permanent equity upon the adoption of FSP EITF 00-19-2. Recorded as a cumulative effect adjustment to the beginning balance of retained earnings. Does not apply to registration payment arrangements that are no longer outstanding upon adoption of FSP EITF 00-19-2.",
        "label": "Reclassifications of Temporary to Permanent Equity",
        "terseLabel": "Reclassification of mezzanine equity to permanent equity"
       }
      }
     },
     "localname": "ReclassificationsOfTemporaryToPermanentEquity",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock": {
     "auth_ref": [
      "r85",
      "r87"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the reconciliation of profit (loss) from reportable segments to the consolidated income (loss) before income tax expense (benefit) and discontinued operations. Includes, but is not limited to, reconciliation after income tax if income tax is allocated to the reportable segment.",
        "label": "Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]",
        "terseLabel": "Reconciliation of U.S. GAAP Income (Loss) Before Income Taxes to Adjusted EBITDA"
       }
      }
     },
     "localname": "ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_RepaymentsOfConvertibleDebt": {
     "auth_ref": [
      "r59"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 1.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.",
        "label": "Repayments of Convertible Debt",
        "negatedLabel": "Repurchase of convertible senior notes"
       }
      }
     },
     "localname": "RepaymentsOfConvertibleDebt",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RepaymentsOfLongTermLinesOfCredit": {
     "auth_ref": [
      "r59"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 7.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.",
        "label": "Repayments of Long-Term Lines of Credit",
        "negatedLabel": "Payments on revolving commitment",
        "terseLabel": "Repayments of borrowing outstanding"
       }
      }
     },
     "localname": "RepaymentsOfLongTermLinesOfCredit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RepaymentsOfNotesPayable": {
     "auth_ref": [
      "r59"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cash outflow for a borrowing supported by a written promise to pay an obligation.",
        "label": "Repayments of Notes Payable",
        "terseLabel": "Repayments of notes payable"
       }
      }
     },
     "localname": "RepaymentsOfNotesPayable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ResearchAndDevelopmentExpense": {
     "auth_ref": [
      "r158",
      "r249",
      "r953"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 0.0,
       "parentTag": "us-gaap_OperatingExpenses",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.",
        "label": "Research and Development Expense",
        "terseLabel": "Research and development",
        "totalLabel": "Research and Development Expense, Total"
       }
      }
     },
     "localname": "ResearchAndDevelopmentExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ResearchAndDevelopmentExpenseMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Primary financial statement caption in which the reported facts about research and development expense have been included.",
        "label": "Research and Development Expense [Member]",
        "terseLabel": "Research and Development [Member]"
       }
      }
     },
     "localname": "ResearchAndDevelopmentExpenseMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ResearchAndDevelopmentExpensePolicy": {
     "auth_ref": [
      "r158"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for costs it has incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process.",
        "label": "Research and Development Expense, Policy [Policy Text Block]",
        "terseLabel": "Research and development costs"
       }
      }
     },
     "localname": "ResearchAndDevelopmentExpensePolicy",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ResearchDevelopmentAndComputerSoftwarePolicyTextBlock": {
     "auth_ref": [
      "r102",
      "r103",
      "r249"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for its research and development and computer software activities including the accounting treatment for costs incurred for (1) research and development activities, (2) development of computer software for internal use, (3) computer software to be sold, leased or otherwise marketed as a separate product or as part of a product or process and (4) in-process research and development acquired in a purchase business combination.",
        "label": "Research, Development, and Computer Software, Policy [Policy Text Block]",
        "terseLabel": "Software development costs"
       }
      }
     },
     "localname": "ResearchDevelopmentAndComputerSoftwarePolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ResearchMember": {
     "auth_ref": [
      "r167"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Research tax credit carryforwards arising from certain qualifying expenditures incurred to develop new products and processes.",
        "label": "Research Tax Credit Carryforward [Member]",
        "terseLabel": "Research and Development Tax Credit Carryforward [Member]"
       }
      }
     },
     "localname": "ResearchMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_RestrictedCashAndCashEquivalentsNoncurrent": {
     "auth_ref": [
      "r67",
      "r72",
      "r764"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.",
        "label": "Restricted Cash and Cash Equivalents, Noncurrent",
        "terseLabel": "Restricted cash included in other long-term assets",
        "totalLabel": "Restricted Cash and Cash Equivalents, Noncurrent, Total"
       }
      }
     },
     "localname": "RestrictedCashAndCashEquivalentsNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RestrictedStockUnitsRSUMember": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Share instrument which is convertible to stock or an equivalent amount of cash, after a specified period of time or when specified performance conditions are met.",
        "label": "Restricted Stock Units (RSUs) [Member]",
        "terseLabel": "Restricted Stock Units (RSUs) [Member]"
       }
      }
     },
     "localname": "RestrictedStockUnitsRSUMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of expected cost remaining for the specified restructuring cost.",
        "label": "Restructuring and Related Cost, Expected Cost Remaining",
        "terseLabel": "Expected remaining restructuring costs"
       }
      }
     },
     "localname": "RestructuringAndRelatedCostExpectedCostRemaining1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RestructuringCharges": {
     "auth_ref": [
      "r65",
      "r429",
      "r430",
      "r880"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail": {
       "order": 4.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.",
        "label": "Restructuring Charges",
        "negatedLabel": "Restructuring expense",
        "terseLabel": "Restructuring costs",
        "totalLabel": "Restructuring Charges, Total"
       }
      }
     },
     "localname": "RestructuringCharges",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RetainedEarningsAccumulatedDeficit": {
     "auth_ref": [
      "r11",
      "r140",
      "r241",
      "r750",
      "r755",
      "r819"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_StockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cumulative amount of the reporting entity's undistributed earnings or deficit.",
        "label": "Retained Earnings (Accumulated Deficit)",
        "terseLabel": "Accumulated deficit",
        "totalLabel": "Retained Earnings (Accumulated Deficit), Total"
       }
      }
     },
     "localname": "RetainedEarningsAccumulatedDeficit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RetainedEarningsMember": {
     "auth_ref": [
      "r252",
      "r308",
      "r309",
      "r310",
      "r314",
      "r322",
      "r324",
      "r401",
      "r581",
      "r582",
      "r583",
      "r613",
      "r614",
      "r653",
      "r746",
      "r748"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The cumulative amount of the reporting entity's undistributed earnings or deficit.",
        "label": "Retained Earnings [Member]",
        "terseLabel": "Accumulated Deficit [Member]"
       }
      }
     },
     "localname": "RetainedEarningsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_RevenueFromContractWithCustomerAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Revenue from Contract with Customer [Abstract]"
       }
      }
     },
     "localname": "RevenueFromContractWithCustomerAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax": {
     "auth_ref": [
      "r356",
      "r357",
      "r369",
      "r374",
      "r375",
      "r381",
      "r382",
      "r385",
      "r515",
      "r516",
      "r726"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 0.0,
       "parentTag": "us-gaap_GrossProfit",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.",
        "label": "Revenue from Contract with Customer, Excluding Assessed Tax",
        "terseLabel": "Total revenue"
       }
      }
     },
     "localname": "RevenueFromContractWithCustomerExcludingAssessedTax",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersScheduleOfDisaggregationOfRevenueParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RevenueFromContractWithCustomerPolicyTextBlock": {
     "auth_ref": [
      "r507",
      "r508",
      "r509",
      "r510",
      "r511",
      "r512",
      "r513",
      "r514",
      "r520",
      "r787"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for revenue from contract with customer.",
        "label": "Revenue from Contract with Customer [Policy Text Block]",
        "terseLabel": "Revenue recognition"
       }
      }
     },
     "localname": "RevenueFromContractWithCustomerPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_RevenueFromContractWithCustomerTextBlock": {
     "auth_ref": [
      "r497",
      "r498",
      "r499",
      "r500",
      "r501",
      "r502",
      "r505",
      "r506",
      "r519",
      "r520"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.",
        "label": "Revenue from Contract with Customer [Text Block]",
        "terseLabel": "Revenue from Contracts with Customers"
       }
      }
     },
     "localname": "RevenueFromContractWithCustomerTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomers"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_RevenueRemainingPerformanceObligation": {
     "auth_ref": [
      "r503"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of transaction price allocated to performance obligation that has not been recognized as revenue.",
        "label": "Revenue, Remaining Performance Obligation, Amount",
        "terseLabel": "Contracted revenue not yet recognized"
       }
      }
     },
     "localname": "RevenueRemainingPerformanceObligation",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1": {
     "auth_ref": [
      "r504"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period",
        "terseLabel": "Revenue, remaining contractual obligation, expected to recognize, period"
       }
      }
     },
     "localname": "RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail1",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis": {
     "auth_ref": [
      "r504"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Start date of time band for expected timing of satisfaction of remaining performance obligation, in YYYY-MM-DD format.",
        "label": "Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]"
       }
      }
     },
     "localname": "RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail1"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_RevenueRemainingPerformanceObligationPercentage": {
     "auth_ref": [
      "r895"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.",
        "label": "Revenue, Remaining Performance Obligation, Percentage",
        "terseLabel": "Revenue recognize percentage"
       }
      }
     },
     "localname": "RevenueRemainingPerformanceObligationPercentage",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Revenues from External Customers and Long-Lived Assets [Line Items]",
        "terseLabel": "Revenues from External Customers and Long-Lived Assets [Line Items]"
       }
      }
     },
     "localname": "RevenuesFromExternalCustomersAndLongLivedAssetsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability": {
     "auth_ref": [
      "r709",
      "r818"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase in right-of-use asset obtained in exchange for finance lease liability.",
        "label": "Right-of-Use Asset Obtained in Exchange for Finance Lease Liability",
        "terseLabel": "Finance leases"
       }
      }
     },
     "localname": "RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalCashFlowInformationRelatedToLeasesDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability": {
     "auth_ref": [
      "r709",
      "r818"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase in right-of-use asset obtained in exchange for operating lease liability.",
        "label": "Right-of-Use Asset Obtained in Exchange for Operating Lease Liability",
        "terseLabel": "Operating leases"
       }
      }
     },
     "localname": "RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureLeasesScheduleOfSupplementalCashFlowInformationRelatedToLeasesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RoyaltyExpense": {
     "auth_ref": [
      "r47"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.",
        "label": "Royalty Expense",
        "terseLabel": "Royalty fees"
       }
      }
     },
     "localname": "RoyaltyExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SaleOfStockNameOfTransactionDomain": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Sale of the entity's stock, including, but not limited to, initial public offering (IPO) and private placement.",
        "label": "Sale of Stock [Domain]"
       }
      }
     },
     "localname": "SaleOfStockNameOfTransactionDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SalesAndExciseTaxPayableCurrentAndNoncurrent": {
     "auth_ref": [
      "r224",
      "r245"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail": {
       "order": 1.0,
       "parentTag": "us-gaap_OtherLiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying value as of the balance sheet date of liabilities incurred through that date and payable for statutory sales and use taxes, including value added tax.",
        "label": "Sales and Excise Tax Payable",
        "terseLabel": "Accrued VAT"
       }
      }
     },
     "localname": "SalesAndExciseTaxPayableCurrentAndNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfOtherAccruedExpensesAndCurrentLiabilitiesDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SalesCommissionsAndFees": {
     "auth_ref": [
      "r48"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Primarily represents commissions incurred in the period based upon the sale by commissioned employees or third parties of the entity's goods or services, and fees for sales assistance or product enhancements performed by third parties (such as a distributor or value added reseller).",
        "label": "Sales Commissions and Fees",
        "terseLabel": "Sales commissions"
       }
      }
     },
     "localname": "SalesCommissionsAndFees",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SalesRevenueNetMember": {
     "auth_ref": [
      "r385",
      "r862"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Revenue from sale of product and rendering of service and other sources of income, when it serves as benchmark in concentration of risk calculation.",
        "label": "Revenue Benchmark [Member]",
        "terseLabel": "Sales Revenue, Net [Member]"
       }
      }
     },
     "localname": "SalesRevenueNetMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable": {
     "auth_ref": [
      "r28"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule itemizing specific types of trade accounts and notes receivable, and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables.",
        "label": "Schedule of Accounts, Notes, Loans and Financing Receivable [Table]",
        "terseLabel": "Schedule Of Accounts Notes Loans And Financing Receivable [Table]"
       }
      }
     },
     "localname": "ScheduleOfAccountsNotesLoansAndFinancingReceivableTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationScheduleOfProvisionForCreditLossDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock": {
     "auth_ref": [
      "r37",
      "r939",
      "r940"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the components of accumulated other comprehensive income (loss).",
        "label": "Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]",
        "terseLabel": "Components of Accumulated Other Comprehensive Loss"
       }
      }
     },
     "localname": "ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock": {
     "auth_ref": [
      "r144"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the amounts that are recognized in the balance sheet (or statement of financial position) for pension plans and/or other employee benefit plans, showing separately the assets and current and noncurrent liabilities (if applicable) recognized.",
        "label": "Schedule of Amounts Recognized in Balance Sheet [Table Text Block]",
        "terseLabel": "Schedule of Pension Benefits Obligation Recorded in Consolidated Balance Sheets"
       }
      }
     },
     "localname": "ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable": {
     "auth_ref": [
      "r75"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule for securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented, by Antidilutive Securities.",
        "label": "Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]",
        "terseLabel": "Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table]"
       }
      }
     },
     "localname": "ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareScheduleOfAntiDilutiveSharesExcludedFromComputationOfDilutedNetLossPerShareDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock": {
     "auth_ref": [
      "r75"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented, by antidilutive securities.",
        "label": "Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]",
        "terseLabel": "Schedule of Anti-dilutive Shares Excluded from Computation of Diluted Net Loss Per Share"
       }
      }
     },
     "localname": "ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable": {
     "auth_ref": [
      "r174",
      "r175",
      "r629"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule reflecting each material business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities.",
        "label": "Schedule of Business Acquisitions, by Acquisition [Table]",
        "terseLabel": "Schedule Of Business Acquisitions By Acquisition [Table]"
       }
      }
     },
     "localname": "ScheduleOfBusinessAcquisitionsByAcquisitionTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock": {
     "auth_ref": [
      "r169"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years.",
        "label": "Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]",
        "terseLabel": "Schedule of Significant Components of Income Tax Expense"
       }
      }
     },
     "localname": "ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock": {
     "auth_ref": [
      "r165"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets.",
        "label": "Schedule of Deferred Tax Assets and Liabilities [Table Text Block]",
        "terseLabel": "Schedule of Deferred Tax Assets and Liabilities"
       }
      }
     },
     "localname": "ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock": {
     "auth_ref": [
      "r861"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations.",
        "label": "Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]",
        "terseLabel": "Computation of Numerators and Denominators Used in Basic and Diluted Net (Loss) Income Per Share Amounts"
       }
      }
     },
     "localname": "ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable": {
     "auth_ref": [
      "r74",
      "r76",
      "r329",
      "r333",
      "r336"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The table contains disclosure pertaining to an entity's basic earnings per share.",
        "label": "Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table]",
        "terseLabel": "Schedule Of Earnings Per Share Basic By Common Class [Table]"
       }
      }
     },
     "localname": "ScheduleOfEarningsPerShareBasicByCommonClassTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock": {
     "auth_ref": [
      "r160"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.",
        "label": "Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]",
        "terseLabel": "Reconciliation of Income Taxes Calculated at U.S. Federal Statutory Income Tax Rate"
       }
      }
     },
     "localname": "ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable": {
     "auth_ref": [
      "r151",
      "r154"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of information about amount recognized for award under share-based payment arrangement. Includes, but is not limited to, amount expensed in statement of income or comprehensive income, amount capitalized in statement of financial position, and corresponding reporting line item in financial statements.",
        "label": "Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]",
        "terseLabel": "Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Table]"
       }
      }
     },
     "localname": "ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock": {
     "auth_ref": [
      "r151"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of allocation of amount expensed and capitalized for award under share-based payment arrangement to statement of income or comprehensive income and statement of financial position. Includes, but is not limited to, corresponding line item in financial statement.",
        "label": "Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]",
        "terseLabel": "Summary of Stock-Based Compensation"
       }
      }
     },
     "localname": "ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock": {
     "auth_ref": [
      "r145"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter.",
        "label": "Schedule of Expected Benefit Payments [Table Text Block]",
        "terseLabel": "Schedule of Estimated Future Benefit Payments"
       }
      }
     },
     "localname": "ScheduleOfExpectedBenefitPaymentsTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRetirementBenefitsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfGoodwillTextBlock": {
     "auth_ref": [
      "r791",
      "r867",
      "r868",
      "r869",
      "r870",
      "r871",
      "r872",
      "r873",
      "r874",
      "r875",
      "r876",
      "r877"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.",
        "label": "Schedule of Goodwill [Table Text Block]",
        "terseLabel": "Changes in Carrying Amount of Goodwill Attributable to Software Reportable Segment"
       }
      }
     },
     "localname": "ScheduleOfGoodwillTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock": {
     "auth_ref": [
      "r849"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of income before income tax between domestic and foreign jurisdictions.",
        "label": "Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]",
        "terseLabel": "Components of Income (Loss) Before Income Taxes"
       }
      }
     },
     "localname": "ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the components of non-operating income or non-operating expense that may include amounts earned from dividends, interest on securities, gains (losses) on securities sold, equity earnings of unconsolidated affiliates, net gain (loss) on sales of business, interest expense and other miscellaneous income or expense items.",
        "label": "Schedule of Other Nonoperating Income (Expense) [Table Text Block]",
        "terseLabel": "Schedule of Other Expense (Income), Net"
       }
      }
     },
     "localname": "ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfPropertyPlantAndEquipmentTable": {
     "auth_ref": [
      "r112"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of information about physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.",
        "label": "Property, Plant and Equipment [Table]",
        "terseLabel": "Schedule Of Property Plant And Equipment [Table]"
       }
      }
     },
     "localname": "ScheduleOfPropertyPlantAndEquipmentTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationSummaryOfPropertyAndEquipmentParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock": {
     "auth_ref": [
      "r178"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the amounts recognized as of the acquisition date for each major class of assets acquired and liabilities assumed. May include but not limited to the following: (a) acquired receivables; (b) contingencies recognized at the acquisition date; and (c) the fair value of noncontrolling interests in the acquiree.",
        "label": "Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]",
        "terseLabel": "Summary of Amounts of Identified Assets Acquired and Liabilities Assumed at the Acquisition Date"
       }
      }
     },
     "localname": "ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTextBlock": {
     "auth_ref": [
      "r72",
      "r215",
      "r240"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of cash and cash equivalents restricted as to withdrawal or usage.",
        "label": "Restrictions on Cash and Cash Equivalents [Table Text Block]",
        "terseLabel": "Reconciliation of Cash, Cash Equivalents and Restricted Cash"
       }
      }
     },
     "localname": "ScheduleOfRestrictedCashAndCashEquivalentsTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock": {
     "auth_ref": [
      "r114",
      "r115",
      "r116"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of costs incurred for restructuring including, but not limited to, exit and disposal activities, remediation, implementation, integration, asset impairment, and charges against earnings from the write-down of assets.",
        "label": "Restructuring and Related Costs [Table Text Block]",
        "terseLabel": "Summary of Restructuring Expense"
       }
      }
     },
     "localname": "ScheduleOfRestructuringAndRelatedCostsTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock": {
     "auth_ref": [
      "r44",
      "r88"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of information concerning material long-lived assets (excluding financial instruments, customer relationships with financial institutions, mortgage and other servicing rights, deferred policy acquisition costs, and deferred taxes assets) located in identified geographic areas and/or the amount of revenue from external customers attributed to that country from which revenue is material. An entity may also provide subtotals of geographic information about groups of countries.",
        "label": "Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block]",
        "terseLabel": "Summary of Sales to External Customers and Long-Lived Assets by Geographical Areas"
       }
      }
     },
     "localname": "ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable": {
     "auth_ref": [
      "r40",
      "r88"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule of material long-lived assets (excluding financial instruments, customer relationships with financial institutions, mortgage and other servicing rights, deferred policy acquisition costs, and deferred taxes assets) located in identified geographic areas and/or the amount of revenue from external customers attributed to that country from which revenue is material. An entity may also provide subtotals of geographic information about groups of countries.",
        "label": "Schedule of Revenues from External Customers and Long-Lived Assets [Table]",
        "terseLabel": "Schedule Of Revenues From External Customers And Long Lived Assets [Table]"
       }
      }
     },
     "localname": "ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfSalesToExternalCustomersAndLongLivedAssetsByGeographicalAreasDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable": {
     "auth_ref": [
      "r83",
      "r84",
      "r86",
      "r91"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A table disclosing the profit or loss and total assets for each reportable segment of the entity. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.",
        "label": "Schedule of Segment Reporting Information, by Segment [Table]",
        "terseLabel": "Schedule Of Segment Reporting Information By Segment [Table]"
       }
      }
     },
     "localname": "ScheduleOfSegmentReportingInformationBySegmentTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock": {
     "auth_ref": [
      "r83",
      "r84",
      "r86",
      "r91"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.",
        "label": "Schedule of Segment Reporting Information, by Segment [Table Text Block]",
        "terseLabel": "Schedule of Segment Reporting Information"
       }
      }
     },
     "localname": "ScheduleOfSegmentReportingInformationBySegmentTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable": {
     "auth_ref": [
      "r542",
      "r544",
      "r547",
      "r548",
      "r549",
      "r551",
      "r552",
      "r553",
      "r554",
      "r555",
      "r556",
      "r557",
      "r558",
      "r559",
      "r560",
      "r561",
      "r562",
      "r563",
      "r564",
      "r565",
      "r566",
      "r567",
      "r568",
      "r571",
      "r572",
      "r573",
      "r574",
      "r575"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of information about share-based payment arrangement.",
        "label": "Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]",
        "terseLabel": "Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]"
       }
      }
     },
     "localname": "ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock": {
     "auth_ref": [
      "r146"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year.",
        "label": "Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]",
        "terseLabel": "Summary of Restricted Stock Units Awarded"
       }
      }
     },
     "localname": "ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock": {
     "auth_ref": [
      "r146",
      "r147",
      "r148"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value.",
        "label": "Share-Based Payment Arrangement, Option, Activity [Table Text Block]",
        "terseLabel": "Summary of Stock Option Activity"
       }
      }
     },
     "localname": "ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock": {
     "auth_ref": [
      "r150"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.",
        "label": "Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]",
        "terseLabel": "Summary of Fair value of Company's Stock Options Granted"
       }
      }
     },
     "localname": "ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfShortTermDebtTable": {
     "auth_ref": [
      "r17"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A table or schedule providing information pertaining to borrowings under which repayment was required in less than twelve months (or normal operating cycle, if longer) after its issuance. It may include: (1) description of the short-term debt arrangement; (2) identification of the lender or type of lender; (3) repayment terms; (4) weighted average interest rate; (5) carrying amount of funds borrowed under the specified short-term debt arrangement as of the balance sheet date and measures of the maximum and average amount outstanding during the period; (6) description of the refinancing of a short-term obligation when that obligation is excluded from current liabilities in the balance sheet; and (7) amount of a short-term obligation that has been excluded from current liabilities in the balance sheet because of a refinancing of the obligation.",
        "label": "Schedule of Short-Term Debt [Table]"
       }
      }
     },
     "localname": "ScheduleOfShortTermDebtTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfStockByClassTable": {
     "auth_ref": [
      "r128",
      "r131",
      "r132",
      "r134",
      "r135",
      "r136",
      "r137",
      "r138",
      "r139",
      "r140",
      "r266",
      "r267",
      "r268",
      "r345",
      "r477",
      "r478",
      "r479",
      "r481",
      "r485",
      "r490",
      "r492",
      "r797",
      "r833",
      "r846"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule detailing information related to equity by class of stock. Class of stock includes common, convertible, and preferred stocks which are not redeemable or redeemable solely at the option of the issuer. It also includes preferred stock with redemption features that are solely within the control of the issuer and mandatorily redeemable stock if redemption is required to occur only upon liquidation or termination of the reporting entity.",
        "label": "Schedule of Stock by Class [Table]",
        "terseLabel": "Schedule Of Stock By Class [Table]"
       }
      }
     },
     "localname": "ScheduleOfStockByClassTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock": {
     "auth_ref": [
      "r814",
      "r926"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the change in unrecognized tax benefits.",
        "label": "Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]",
        "terseLabel": "Reconciliation of Beginning and Ending Amounts of Unrecognized Tax Benefits"
       }
      }
     },
     "localname": "ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock": {
     "auth_ref": [
      "r98"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of the amount of amortization expense expected to be recorded in succeeding fiscal years for finite-lived intangible assets.",
        "label": "Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]",
        "terseLabel": "Summary of Estimated Amortization Expense"
       }
      }
     },
     "localname": "ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember": {
     "auth_ref": [
      "r935"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Fixed rate on U.S. dollar, constant-notional interest rate swap that has its variable-rate leg referenced to Secured Overnight Financing Rate (SOFR) with no additional spread over SOFR on variable-rate leg.",
        "label": "Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]"
       }
      }
     },
     "localname": "SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SegmentDomain": {
     "auth_ref": [
      "r353",
      "r356",
      "r357",
      "r358",
      "r359",
      "r360",
      "r361",
      "r362",
      "r363",
      "r364",
      "r365",
      "r366",
      "r367",
      "r369",
      "r370",
      "r371",
      "r372",
      "r373",
      "r374",
      "r375",
      "r376",
      "r377",
      "r379",
      "r385",
      "r410",
      "r411",
      "r412",
      "r413",
      "r414",
      "r415",
      "r416",
      "r417",
      "r418",
      "r428",
      "r431",
      "r791",
      "r955"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Components of an entity that engage in business activities from which they may earn revenue and incur expenses, including transactions with other components of the same entity.",
        "label": "Segments [Domain]",
        "terseLabel": "Segments"
       }
      }
     },
     "localname": "SegmentDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SegmentReportingAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Segment Reporting [Abstract]"
       }
      }
     },
     "localname": "SegmentReportingAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_SegmentReportingDisclosureTextBlock": {
     "auth_ref": [
      "r353",
      "r354",
      "r355",
      "r365",
      "r368",
      "r373",
      "r377",
      "r378",
      "r379",
      "r380",
      "r381",
      "r384",
      "r385",
      "r386"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.",
        "label": "Segment Reporting Disclosure [Text Block]",
        "terseLabel": "Segment Information"
       }
      }
     },
     "localname": "SegmentReportingDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformation"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SegmentReportingInformationLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Segment Reporting Information [Line Items]",
        "terseLabel": "Segment Reporting Information [Line Items]"
       }
      }
     },
     "localname": "SegmentReportingInformationLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_SellingAndMarketingExpense": {
     "auth_ref": [],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations": {
       "order": 1.0,
       "parentTag": "us-gaap_OperatingExpenses",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The aggregate total amount of expenses directly related to the marketing or selling of products or services.",
        "label": "Selling and Marketing Expense",
        "terseLabel": "Sales and marketing",
        "totalLabel": "Selling and Marketing Expense, Total"
       }
      }
     },
     "localname": "SellingAndMarketingExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SellingAndMarketingExpenseMember": {
     "auth_ref": [
      "r43"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Primary financial statement caption encompassing selling and marketing expense.",
        "label": "Selling and Marketing Expense [Member]",
        "terseLabel": "Sales and Marketing Expense [Member]",
        "verboseLabel": "Sales and marketing [Member]"
       }
      }
     },
     "localname": "SellingAndMarketingExpenseMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureRevenueFromContractsWithCustomersAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SeveranceCosts1": {
     "auth_ref": [
      "r65"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.",
        "label": "Severance Costs",
        "terseLabel": "Severance expense"
       }
      }
     },
     "localname": "SeveranceCosts1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDAParentheticalDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensation": {
     "auth_ref": [
      "r64"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail": {
       "order": 1.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
       "weight": -1.0
      },
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows": {
       "order": 3.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of noncash expense for share-based payment arrangement.",
        "label": "Share-Based Payment Arrangement, Noncash Expense",
        "negatedLabel": "Stock-based compensation expense",
        "terseLabel": "Stock-based compensation expense",
        "totalLabel": "Share-Based Payment Arrangement, Noncash Expense, Total",
        "verboseLabel": "Total stock-based compensation expense"
       }
      }
     },
     "localname": "ShareBasedCompensation",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfUSGAAPIncomeLossBeforeIncomeTaxesToAdjustedEBITDADetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockBasedCompensationExpenseDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1": {
     "auth_ref": [
      "r811"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period",
        "terseLabel": "Stock-based compensation awards requisite service period",
        "verboseLabel": "Weighted average remaining service period"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod": {
     "auth_ref": [
      "r564"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period",
        "negatedLabel": "Number of RSUs, Forfeited"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod": {
     "auth_ref": [
      "r562"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period",
        "terseLabel": "Number of RSUs, Granted"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber": {
     "auth_ref": [
      "r559",
      "r560"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number",
        "periodEndLabel": "Number of RSUs, Outstanding Ending Balance",
        "periodStartLabel": "Number of RSUs, Outstanding Beginning Balance"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]",
        "terseLabel": "Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue": {
     "auth_ref": [
      "r559",
      "r560"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value",
        "periodEndLabel": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value, Ending Balance",
        "periodStartLabel": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value, Beginning Balance",
        "terseLabel": "Weighted average grant date fair value of RSUs"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod": {
     "auth_ref": [
      "r563"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period",
        "negatedLabel": "Number of RSUs, Vested"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue": {
     "auth_ref": [
      "r566"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value",
        "verboseLabel": "Fair value of RSUs vested"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate": {
     "auth_ref": [
      "r573"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate",
        "terseLabel": "Expected dividend yield"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate": {
     "auth_ref": [
      "r572"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate",
        "terseLabel": "Expected volatility"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum",
        "terseLabel": "Expected volatility, maximum"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum",
        "terseLabel": "Expected volatility, minimum"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate": {
     "auth_ref": [
      "r574"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The risk-free interest rate assumption that is used in valuing an option on its own shares.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate",
        "terseLabel": "Risk-free interest rate"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum",
        "terseLabel": "Risk-free interest rate, maximum"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum",
        "terseLabel": "Risk-free interest rate, minimum"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]",
        "terseLabel": "Share-based Compensation Arrangement by Share-based Payment Award [Line Items]"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate": {
     "auth_ref": [
      "r152"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Maximum Employee Subscription Rate",
        "terseLabel": "Percentage of eligible compensation for employee payroll deductions"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized": {
     "auth_ref": [
      "r813"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of shares authorized for issuance under share-based payment arrangement.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized",
        "terseLabel": "Shares authorized"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Additional Disclosures [Abstract]",
        "terseLabel": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber": {
     "auth_ref": [
      "r553"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number",
        "terseLabel": "Number of options, Exercisable"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice": {
     "auth_ref": [
      "r553"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price",
        "terseLabel": "Weighted average exercise price per share, Exercisable"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue": {
     "auth_ref": [
      "r566"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value",
        "terseLabel": "Intrinsic value of options exercised"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod": {
     "auth_ref": [
      "r557"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures in Period",
        "negatedLabel": "Number of options, Forfeited"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross": {
     "auth_ref": [
      "r555"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Gross number of share options (or share units) granted during the period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross",
        "terseLabel": "Number of options, Granted"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue": {
     "auth_ref": [
      "r565"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value",
        "terseLabel": "Weighted average grant date fair value per share"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue": {
     "auth_ref": [
      "r152"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value",
        "terseLabel": "Aggregate intrinsic value, Outstanding"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber": {
     "auth_ref": [
      "r551",
      "r552"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of options outstanding, including both vested and non-vested options.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number",
        "periodEndLabel": "Number of options, Outstanding, Ending Balance",
        "periodStartLabel": "Number of options, Outstanding, Beginning Balance",
        "terseLabel": "Number of options, outstanding"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward]",
        "terseLabel": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice": {
     "auth_ref": [
      "r551",
      "r552"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price",
        "periodEndLabel": "Weighted average exercise price per share, Outstanding, Ending Balance",
        "periodStartLabel": "Weighted average exercise price per share, Outstanding, Beginning Balance",
        "terseLabel": "Exercise price stock options outstanding"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]",
        "terseLabel": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain": {
     "auth_ref": [
      "r547",
      "r548",
      "r549",
      "r551",
      "r552",
      "r553",
      "r554",
      "r555",
      "r556",
      "r557",
      "r558",
      "r559",
      "r560",
      "r561",
      "r562",
      "r563",
      "r564",
      "r565",
      "r566",
      "r567",
      "r568",
      "r571",
      "r572",
      "r573",
      "r574",
      "r575"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Award under share-based payment arrangement.",
        "label": "Award Type [Domain]",
        "terseLabel": "Award Type"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfRestrictedStockUnitsAwardedDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice": {
     "auth_ref": [
      "r556"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average price at which option holders acquired shares when converting their stock options into shares.",
        "label": "Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price",
        "terseLabel": "Weighted average exercise price per share, Exercised"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice": {
     "auth_ref": [
      "r557"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.",
        "label": "Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price",
        "terseLabel": "Weighted average exercise price per share, Forfeited"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice": {
     "auth_ref": [
      "r555"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.",
        "label": "Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price",
        "terseLabel": "Weighted average exercise price per share, Granted"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy": {
     "auth_ref": [
      "r550",
      "r569",
      "r570",
      "r571",
      "r572",
      "r575",
      "r584",
      "r585"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for award under share-based payment arrangement. Includes, but is not limited to, methodology and assumption used in measuring cost.",
        "label": "Share-Based Payment Arrangement [Policy Text Block]",
        "terseLabel": "Stock-based compensation"
       }
      }
     },
     "localname": "ShareBasedCompensationOptionAndIncentivePlansPolicy",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ShareBasedPaymentArrangementEmployeeMember": {
     "auth_ref": [
      "r544",
      "r547",
      "r548",
      "r549",
      "r551",
      "r552",
      "r553",
      "r554",
      "r555",
      "r556",
      "r557",
      "r558",
      "r559",
      "r560",
      "r561",
      "r562",
      "r563",
      "r564",
      "r565",
      "r566",
      "r567",
      "r568",
      "r571",
      "r572",
      "r573",
      "r574",
      "r575"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Recipient, of award granted under share-based payment arrangement, over whom grantor exercises or has right to exercise sufficient control to establish employer-employee relationship based on law of pertinent jurisdiction. Includes, but is not limited to, nonemployee director treated as employee when acting as member of board of directors, if elected by grantor's shareholders or appointed to board position to be filled by shareholder election when existing term expires.",
        "label": "Share-Based Payment Arrangement, Employee [Member]",
        "terseLabel": "Employee [Member]"
       }
      }
     },
     "localname": "ShareBasedPaymentArrangementEmployeeMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod": {
     "auth_ref": [
      "r812"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period",
        "terseLabel": "Contractual term"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1": {
     "auth_ref": [
      "r571"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term",
        "terseLabel": "Expected term (in years)"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfFairValueOfCompanySStockOptionsGrantedDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1": {
     "auth_ref": [
      "r152"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value",
        "terseLabel": "Aggregate intrinsic value, Exercisable"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1": {
     "auth_ref": [
      "r152"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term",
        "terseLabel": "Weighted average remaining contractual term (years), Exercisable"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2": {
     "auth_ref": [
      "r149"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term",
        "terseLabel": "Weighted average remaining contractual term (years), Outstanding"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Purchase price of common stock expressed as a percentage of its fair value.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent",
        "terseLabel": "Percentage of purchase price for each share of common stock purchased of lower of fair market value per share on first day of applicable offering period"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_SharesOutstanding": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of shares issued which are neither cancelled nor held in the treasury.",
        "label": "Shares, Outstanding",
        "periodEndLabel": "Ending balance (in shares)",
        "periodStartLabel": "Beginning balance (in shares)"
       }
      }
     },
     "localname": "SharesOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_SignificantAccountingPoliciesTextBlock": {
     "auth_ref": [
      "r73",
      "r293"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for all significant accounting policies of the reporting entity.",
        "label": "Significant Accounting Policies [Text Block]",
        "terseLabel": "Summary of Significant Accounting Policies"
       }
      }
     },
     "localname": "SignificantAccountingPoliciesTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit": {
     "auth_ref": [
      "r161"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.",
        "label": "Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit",
        "terseLabel": "Reduction in unrecognized tax benefits which if recognized would not impact effective tax rate in next 12 months"
       }
      }
     },
     "localname": "SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StatementBusinessSegmentsAxis": {
     "auth_ref": [
      "r255",
      "r353",
      "r356",
      "r357",
      "r358",
      "r359",
      "r360",
      "r361",
      "r362",
      "r363",
      "r364",
      "r365",
      "r366",
      "r367",
      "r369",
      "r370",
      "r371",
      "r372",
      "r373",
      "r374",
      "r375",
      "r376",
      "r377",
      "r379",
      "r385",
      "r410",
      "r411",
      "r412",
      "r413",
      "r414",
      "r415",
      "r416",
      "r417",
      "r418",
      "r426",
      "r428",
      "r431",
      "r791",
      "r955"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by business segments.",
        "label": "Segments [Axis]",
        "terseLabel": "Segments"
       }
      }
     },
     "localname": "StatementBusinessSegmentsAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSegmentInformationScheduleOfSegmentReportingInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementClassOfStockAxis": {
     "auth_ref": [
      "r266",
      "r267",
      "r268",
      "r296",
      "r329",
      "r333",
      "r336",
      "r338",
      "r345",
      "r346",
      "r394",
      "r439",
      "r441",
      "r442",
      "r443",
      "r446",
      "r447",
      "r477",
      "r478",
      "r481",
      "r485",
      "r492",
      "r659",
      "r782",
      "r833",
      "r846",
      "r860"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by the different classes of stock of the entity.",
        "label": "Class of Stock [Axis]",
        "terseLabel": "Class of Stock"
       }
      }
     },
     "localname": "StatementClassOfStockAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DocumentDocumentAndEntityInformation",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementEquityComponentsAxis": {
     "auth_ref": [
      "r27",
      "r133",
      "r252",
      "r279",
      "r280",
      "r281",
      "r308",
      "r309",
      "r310",
      "r314",
      "r322",
      "r324",
      "r344",
      "r401",
      "r493",
      "r581",
      "r582",
      "r583",
      "r613",
      "r614",
      "r653",
      "r675",
      "r676",
      "r677",
      "r678",
      "r679",
      "r682",
      "r718",
      "r746",
      "r747",
      "r748"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by component of equity.",
        "label": "Equity Components [Axis]",
        "terseLabel": "Equity Components"
       }
      }
     },
     "localname": "StatementEquityComponentsAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Statement [Line Items]",
        "terseLabel": "Statement [Line Items]"
       }
      }
     },
     "localname": "StatementLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementOfCashFlowsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Statement of Cash Flows [Abstract]"
       }
      }
     },
     "localname": "StatementOfCashFlowsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementOfFinancialPositionAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Statement of Financial Position [Abstract]"
       }
      }
     },
     "localname": "StatementOfFinancialPositionAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Statement of Comprehensive Income [Abstract]",
        "terseLabel": "Statement Of Income And Comprehensive Income [Abstract]"
       }
      }
     },
     "localname": "StatementOfIncomeAndComprehensiveIncomeAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncome",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfComprehensiveLossIncomeParenthetical"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementOfStockholdersEquityAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Statement of Stockholders' Equity [Abstract]"
       }
      }
     },
     "localname": "StatementOfStockholdersEquityAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementTable": {
     "auth_ref": [
      "r308",
      "r309",
      "r310",
      "r344",
      "r726"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Schedule reflecting a Statement of Income, Statement of Cash Flows, Statement of Financial Position, Statement of Shareholders' Equity and Other Comprehensive Income, or other statement as needed.",
        "label": "Statement [Table]",
        "terseLabel": "Statement [Table]"
       }
      }
     },
     "localname": "StatementTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationTables",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StockIssuedDuringPeriodSharesAcquisitions": {
     "auth_ref": [
      "r8",
      "r9",
      "r140"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of shares of stock issued during the period pursuant to acquisitions.",
        "label": "Stock Issued During Period, Shares, Acquisitions",
        "terseLabel": "Issuance of common stock for acquisitions (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesAcquisitions",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans": {
     "auth_ref": [
      "r8",
      "r9",
      "r133",
      "r140"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of shares issued during the period as a result of an employee stock purchase plan.",
        "label": "Stock Issued During Period, Shares, Employee Stock Purchase Plans",
        "terseLabel": "Purchases related to ESPP",
        "verboseLabel": "Issuance of common stock for employee stock purchase program (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockIssuedDuringPeriodSharesNewIssues": {
     "auth_ref": [
      "r8",
      "r9",
      "r133",
      "r140"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of new stock issued during the period.",
        "label": "Stock Issued During Period, Shares, New Issues",
        "terseLabel": "Stock issued"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesNewIssues",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures": {
     "auth_ref": [
      "r8",
      "r9",
      "r133",
      "r140"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.",
        "label": "Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures",
        "terseLabel": "Vesting of restricted stock (in shares)",
        "totalLabel": "Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised": {
     "auth_ref": [
      "r8",
      "r9",
      "r133",
      "r140",
      "r556"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of share options (or share units) exercised during the current period.",
        "label": "Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period",
        "negatedLabel": "Number of options, Exercised",
        "terseLabel": "Exercise of stock options (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesStockOptionsExercised",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2012PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnder2017PlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityUnderNSOPlanDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockIssuedDuringPeriodValueAcquisitions": {
     "auth_ref": [
      "r27",
      "r133",
      "r140"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Value of stock issued pursuant to acquisitions during the period.",
        "label": "Stock Issued During Period, Value, Acquisitions",
        "terseLabel": "Issuance of common stock for acquisitions"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValueAcquisitions",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan": {
     "auth_ref": [
      "r8",
      "r9",
      "r133",
      "r140"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.",
        "label": "Stock Issued During Period, Value, Employee Stock Purchase Plan",
        "terseLabel": "Stock purchase plan agreement",
        "verboseLabel": "Issuance of common stock for employee stock purchase program"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValueEmployeeStockPurchasePlan",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised": {
     "auth_ref": [
      "r27",
      "r133",
      "r140"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Value of stock issued as a result of the exercise of stock options.",
        "label": "Stock Issued During Period, Value, Stock Options Exercised",
        "terseLabel": "Exercise of stock options"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValueStockOptionsExercised",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StockRepurchaseProgramAuthorizedAmount1": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of stock repurchase plan authorized.",
        "label": "Stock Repurchase Program, Authorized Amount",
        "terseLabel": "Shares authorized to be repurchased amount"
       }
      }
     },
     "localname": "StockRepurchaseProgramAuthorizedAmount1",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.",
        "label": "Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased",
        "terseLabel": "Stock repurchase program, Repurchase Shares"
       }
      }
     },
     "localname": "StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockholdersEquity": {
     "auth_ref": [
      "r9",
      "r12",
      "r13",
      "r90",
      "r819",
      "r848",
      "r864",
      "r938"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.",
        "label": "Stockholders' Equity Attributable to Parent",
        "periodEndLabel": "Ending balance",
        "periodStartLabel": "Beginning balance",
        "totalLabel": "TOTAL STOCKHOLDERS\u2019 EQUITY"
       }
      }
     },
     "localname": "StockholdersEquity",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAccumulatedOtherComprehensiveLossComponentsOfAccumulatedOtherComprehensiveLossDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementOfChangesInStockholdersEquityDeficit"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StockholdersEquityAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Stockholders' Equity Attributable to Parent [Abstract]",
        "terseLabel": "STOCKHOLDERS\u2019 EQUITY"
       }
      }
     },
     "localname": "StockholdersEquityAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StockholdersEquityNoteDisclosureTextBlock": {
     "auth_ref": [
      "r141",
      "r295",
      "r478",
      "r480",
      "r481",
      "r482",
      "r483",
      "r484",
      "r485",
      "r486",
      "r487",
      "r488",
      "r489",
      "r491",
      "r493",
      "r644"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.",
        "label": "Stockholders' Equity Note Disclosure [Text Block]",
        "terseLabel": "Stockholders' Equity"
       }
      }
     },
     "localname": "StockholdersEquityNoteDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquity"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SubsequentEventMember": {
     "auth_ref": [
      "r683",
      "r721"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Identifies event that occurred after the balance sheet date but before financial statements are issued or available to be issued.",
        "label": "Subsequent Event [Member]",
        "terseLabel": "Subsequent Event [Member]"
       }
      }
     },
     "localname": "SubsequentEventMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SubsequentEventTypeAxis": {
     "auth_ref": [
      "r683",
      "r721"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by event that occurred after the balance sheet date but before financial statements are issued or available to be issued.",
        "label": "Subsequent Event Type [Axis]",
        "terseLabel": "Subsequent Event Type"
       }
      }
     },
     "localname": "SubsequentEventTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_SubsequentEventTypeDomain": {
     "auth_ref": [
      "r683",
      "r721"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Event that occurred after the balance sheet date but before financial statements are issued or available to be issued.",
        "label": "Subsequent Event Type [Domain]",
        "terseLabel": "Subsequent Event Type"
       }
      }
     },
     "localname": "SubsequentEventTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SubsequentEventsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Subsequent Events [Abstract]"
       }
      }
     },
     "localname": "SubsequentEventsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "xbrltype": "stringItemType"
    },
    "us-gaap_SubsequentEventsTextBlock": {
     "auth_ref": [
      "r720",
      "r722"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.",
        "label": "Subsequent Events [Text Block]",
        "terseLabel": "Subsequent Events"
       }
      }
     },
     "localname": "SubsequentEventsTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSubsequentEvents"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SubsidiarySaleOfStockAxis": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of sale of the entity's stock.",
        "label": "Sale of Stock [Axis]"
       }
      }
     },
     "localname": "SubsidiarySaleOfStockAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSupplementaryInformationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_SummaryOfValuationAllowanceTextBlock": {
     "auth_ref": [
      "r164"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of valuation allowances to reduce deferred tax assets to net realizable value, including identification of the deferred tax asset more likely than not will not be fully realized and the corresponding amount of the valuation allowance.",
        "label": "Summary of Valuation Allowance [Table Text Block]",
        "terseLabel": "Summary of Changes to Valuation Allowance Balance"
       }
      }
     },
     "localname": "SummaryOfValuationAllowanceTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SupplementalCashFlowInformationAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Supplemental Cash Flow Information [Abstract]",
        "terseLabel": "Supplemental disclosures of cash flow:"
       }
      }
     },
     "localname": "SupplementalCashFlowInformationAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_TaxCreditCarryforwardAmount": {
     "auth_ref": [
      "r166"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.",
        "label": "Tax Credit Carryforward, Amount",
        "terseLabel": "Tax credit carryforward"
       }
      }
     },
     "localname": "TaxCreditCarryforwardAmount",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_TaxCreditCarryforwardAxis": {
     "auth_ref": [
      "r167"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by specific tax credit related to an unused tax credit.",
        "label": "Tax Credit Carryforward [Axis]",
        "terseLabel": "Tax Credit Carryforward"
       }
      }
     },
     "localname": "TaxCreditCarryforwardAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_TaxCreditCarryforwardNameDomain": {
     "auth_ref": [
      "r167"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The name of the tax credit carryforward.",
        "label": "Tax Credit Carryforward, Name [Domain]",
        "terseLabel": "Tax Credit Carryforward, Name"
       }
      }
     },
     "localname": "TaxCreditCarryforwardNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesOperatingLossAndTaxCreditCarryforwardsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_TemporaryEquityCarryingAmountAttributableToParent": {
     "auth_ref": [
      "r439",
      "r441",
      "r442",
      "r443",
      "r446",
      "r447"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.",
        "label": "Temporary Equity, Carrying Amount, Attributable to Parent",
        "terseLabel": "MEZZANINE EQUITY"
       }
      }
     },
     "localname": "TemporaryEquityCarryingAmountAttributableToParent",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_TemporaryEquityRedemptionPricePerShare": {
     "auth_ref": [
      "r0",
      "r129"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount to be paid per share that is classified as temporary equity by entity upon redemption. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.",
        "label": "Temporary Equity, Redemption Price Per Share",
        "terseLabel": "Put right, exercise price"
       }
      }
     },
     "localname": "TemporaryEquityRedemptionPricePerShare",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_TemporaryEquitySharesIssued": {
     "auth_ref": [
      "r7"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.",
        "label": "Temporary Equity, Shares Issued",
        "terseLabel": "Shares issued"
       }
      }
     },
     "localname": "TemporaryEquitySharesIssued",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_TradeNamesMember": {
     "auth_ref": [
      "r179"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Rights acquired through registration of a business name to gain or protect exclusive use thereof.",
        "label": "Trade Names [Member]",
        "terseLabel": "Trade Names [Member]"
       }
      }
     },
     "localname": "TradeNamesMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsSummaryOfAmountsOfIdentifiedAssetsAcquiredAndLiabilitiesAssumedAtAcquisitionDateParentheticalDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsScheduleOfOtherIntangibleAssetsDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_TreasuryStockSharesAcquired": {
     "auth_ref": [
      "r9",
      "r133",
      "r140"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of shares that have been repurchased during the period and are being held in treasury.",
        "label": "Treasury Stock, Shares, Acquired",
        "terseLabel": "Number of shares repurchased"
       }
      }
     },
     "localname": "TreasuryStockSharesAcquired",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockholdersEquityAdditionalInformationDetail"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_TypeOfAdoptionMember": {
     "auth_ref": [
      "r250",
      "r251",
      "r252",
      "r253",
      "r254",
      "r313",
      "r314",
      "r315",
      "r316",
      "r326",
      "r390",
      "r391",
      "r398",
      "r399",
      "r400",
      "r401",
      "r403",
      "r404",
      "r581",
      "r582",
      "r583",
      "r611",
      "r612",
      "r613",
      "r614",
      "r631",
      "r632",
      "r633",
      "r645",
      "r646",
      "r647",
      "r648",
      "r649",
      "r650",
      "r651",
      "r652",
      "r653",
      "r654",
      "r655",
      "r656",
      "r660",
      "r661",
      "r663",
      "r664",
      "r665",
      "r666",
      "r667",
      "r668",
      "r687",
      "r688",
      "r693",
      "r694",
      "r695",
      "r696",
      "r713",
      "r714",
      "r715",
      "r716",
      "r717",
      "r718",
      "r728",
      "r729",
      "r730",
      "r744",
      "r745",
      "r746",
      "r747",
      "r748",
      "r749",
      "r750",
      "r751",
      "r752",
      "r753",
      "r754",
      "r755"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amendment to accounting standards.",
        "label": "Accounting Standards Update [Domain]",
        "terseLabel": "Accounting Standards Update"
       }
      }
     },
     "localname": "TypeOfAdoptionMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_TypeOfArrangementAxis": {
     "auth_ref": [
      "r932"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by collaborative arrangement and arrangement other than collaborative applicable to revenue-generating activity or operations.",
        "label": "Collaborative Arrangement and Arrangement Other than Collaborative [Axis]",
        "terseLabel": "Collaborative Arrangement and Arrangement Other than Collaborative"
       }
      }
     },
     "localname": "TypeOfArrangementAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureAcquisitionsAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_UnrecognizedTaxBenefits": {
     "auth_ref": [
      "r588",
      "r597"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of unrecognized tax benefits.",
        "label": "Unrecognized Tax Benefits",
        "periodEndLabel": "Unrecognized tax benefits\u2014December 31",
        "periodStartLabel": "Unrecognized tax benefits-January 1"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefits",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfBeginningAndEndingAmountsOfUnrecognizedTaxBenefitsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromCurrentPeriodTaxPositions": {
     "auth_ref": [
      "r163"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.",
        "label": "Unrecognized Tax Benefits, Decrease Resulting from Current Period Tax Positions",
        "terseLabel": "Additions (reductions) for tax positions of current period"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefitsDecreasesResultingFromCurrentPeriodTaxPositions",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfBeginningAndEndingAmountsOfUnrecognizedTaxBenefitsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions": {
     "auth_ref": [
      "r598"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.",
        "label": "Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions",
        "negatedLabel": "Reductions for tax positions of prior periods"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfBeginningAndEndingAmountsOfUnrecognizedTaxBenefitsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued": {
     "auth_ref": [
      "r596"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.",
        "label": "Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued",
        "terseLabel": "Accrued interest and penalties related to unrecognized tax benefits",
        "totalLabel": "Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions": {
     "auth_ref": [
      "r598"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.",
        "label": "Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions",
        "terseLabel": "Additions for tax positions of prior periods"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfBeginningAndEndingAmountsOfUnrecognizedTaxBenefitsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations": {
     "auth_ref": [
      "r599"
     ],
     "crdr": "debit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.",
        "label": "Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations",
        "negatedLabel": "Reductions due to statute of limitations"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesReconciliationOfBeginningAndEndingAmountsOfUnrecognizedTaxBenefitsDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate": {
     "auth_ref": [
      "r600"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.",
        "label": "Unrecognized Tax Benefits that Would Impact Effective Tax Rate",
        "terseLabel": "Gross unrecognized tax benefits recognized would affect the effective tax rate"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecordedUnconditionalPurchaseObligationsDisclosureTextBlock": {
     "auth_ref": [
      "r881"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Tabular disclosure of unconditional purchase obligation not recognized as liability.",
        "label": "Unrecorded Unconditional Purchase Obligations Disclosure [Table Text Block]",
        "terseLabel": "Future Purchase Obligations"
       }
      }
     },
     "localname": "UnrecordedUnconditionalPurchaseObligationsDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_UseOfEstimates": {
     "auth_ref": [
      "r80",
      "r81",
      "r82",
      "r348",
      "r349",
      "r350",
      "r351"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.",
        "label": "Use of Estimates, Policy [Policy Text Block]",
        "terseLabel": "Use of estimates"
       }
      }
     },
     "localname": "UseOfEstimates",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ValuationAllowanceLineItems": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.",
        "label": "Valuation Allowance [Line Items]",
        "terseLabel": "Valuation Allowance [Line Items]"
       }
      }
     },
     "localname": "ValuationAllowanceLineItems",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ValuationAllowanceOfDeferredTaxAssetsMember": {
     "auth_ref": [
      "r850",
      "r851",
      "r852",
      "r853",
      "r854"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Valuation allowance of deferred tax asset attributable to deductible temporary difference and carryforward.",
        "label": "SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member]",
        "terseLabel": "Valuation Allowance of Deferred Tax Assets [Member]"
       }
      }
     },
     "localname": "ValuationAllowanceOfDeferredTaxAssetsMember",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ValuationAllowanceTable": {
     "auth_ref": [
      "r164"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "A listing of an entity's valuation allowances to reduce deferred tax assets to amounts which it is more likely than not will not be realized, including a description of the deferred tax assets for which the valuation allowance has been recorded and the amount of the valuation allowance.",
        "label": "Valuation Allowance [Table]",
        "terseLabel": "Valuation Allowance [Table]"
       }
      }
     },
     "localname": "ValuationAllowanceTable",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ValuationAllowancesAndReservesBalance": {
     "auth_ref": [
      "r301",
      "r307"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of valuation and qualifying accounts and reserves.",
        "label": "SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount",
        "periodEndLabel": "Balance at end of year",
        "periodStartLabel": "Balance at beginning of year"
       }
      }
     },
     "localname": "ValuationAllowancesAndReservesBalance",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense": {
     "auth_ref": [
      "r304"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.",
        "label": "SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense",
        "verboseLabel": "Additions charged to expense"
       }
      }
     },
     "localname": "ValuationAllowancesAndReservesChargedToCostAndExpense",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts": {
     "auth_ref": [
      "r305"
     ],
     "crdr": "credit",
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Amount of increase in valuation and qualifying accounts and reserves from charge to accounts other than cost and expense.",
        "label": "SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account",
        "terseLabel": "Valuation allowance in other",
        "verboseLabel": "Other"
       }
      }
     },
     "localname": "ValuationAllowancesAndReservesChargedToOtherAccounts",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ValuationAllowancesAndReservesDomain": {
     "auth_ref": [
      "r301",
      "r302",
      "r303",
      "r306",
      "r307"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Valuation and qualifying accounts and reserves.",
        "label": "SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain]",
        "terseLabel": "SEC Schedule, 12-09, Valuation Allowances and Reserves"
       }
      }
     },
     "localname": "ValuationAllowancesAndReservesDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ValuationAllowancesAndReservesTypeAxis": {
     "auth_ref": [
      "r301",
      "r302",
      "r303",
      "r306",
      "r307"
     ],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by valuation and qualifying accounts and reserves.",
        "label": "SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis]",
        "terseLabel": "SEC Schedule, 12-09, Valuation Allowances and Reserves Type"
       }
      }
     },
     "localname": "ValuationAllowancesAndReservesTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesToValuationAllowanceBalanceDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_VariableRateAxis": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Information by type of variable rate.",
        "label": "Variable Rate [Axis]",
        "terseLabel": "Variable Rate"
       }
      }
     },
     "localname": "VariableRateAxis",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_VariableRateDomain": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Interest rate that fluctuates over time as a result of an underlying benchmark interest rate or index.",
        "label": "Variable Rate [Domain]",
        "terseLabel": "Variable Rate"
       }
      }
     },
     "localname": "VariableRateDomain",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding": {
     "auth_ref": [
      "r328",
      "r338"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "lang": {
      "en-us": {
       "role": {
        "documentation": "The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.",
        "label": "Weighted Average Number of Shares Outstanding, Diluted",
        "terseLabel": "Weighted average number of shares used in computing net loss per share, diluted",
        "totalLabel": "Denominator for dilutive loss per share"
       }
      }
     },
     "localname": "WeightedAverageNumberOfDilutedSharesOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Weighted Average Number of Shares Outstanding, Diluted [Abstract]",
        "terseLabel": "Weighted average shares outstanding:"
       }
      }
     },
     "localname": "WeightedAverageNumberOfSharesOutstandingAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_WeightedAverageNumberOfSharesOutstandingBasic": {
     "auth_ref": [
      "r327",
      "r338"
     ],
     "calculation": {
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail": {
       "order": 0.0,
       "parentTag": "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding",
       "weight": 1.0
      }
     },
     "lang": {
      "en-us": {
       "role": {
        "documentation": "Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.",
        "label": "Weighted Average Number of Shares Outstanding, Basic",
        "terseLabel": "Weighted average number of shares used in computing net loss per share, basic",
        "totalLabel": "Weighted Average Number of Shares Outstanding, Basic, Total",
        "verboseLabel": "Denominator for basic loss per share \u2014 weighted average shares"
       }
      }
     },
     "localname": "WeightedAverageNumberOfSharesOutstandingBasic",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail",
      "http://www.altair.com/20221231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-us": {
       "role": {
        "label": "Weighted Average Number of Shares Outstanding Reconciliation [Abstract]",
        "terseLabel": "Denominator:"
       }
      }
     },
     "localname": "WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2022",
     "presentation": [
      "http://www.altair.com/20221231/taxonomy/role/Role_DisclosureNetLossPerShareComputationOfNumeratorsAndDenominatorsUsedInBasicAndDilutedNetLossIncomePerShareAmountsDetail"
     ],
     "xbrltype": "stringItemType"
    }
   },
   "unitCount": 11
  }
 },
 "std_ref": {
  "r0": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(27)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r1": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(19))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r10": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(30)(a)(1))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r100": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(2)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r101": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r102": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "30",
   "SubTopic": "40",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=118172244&loc=d3e17916-109280",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r103": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "50",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=16397303&loc=d3e19347-109286",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r104": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "350",
   "URI": "https://asc.fasb.org/topic&trid=2144416",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r105": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "05",
   "SubTopic": "10",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=109226317&loc=d3e202-110218",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r106": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "15",
   "SubTopic": "10",
   "Subparagraph": "(b)(2)",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=126982154&loc=d3e400-110220",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r107": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "35",
   "SubTopic": "10",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=126905813&loc=d3e1205-110223",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r108": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=126905981&loc=d3e2420-110228",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r109": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r11": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(30)(a)(3))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r110": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r111": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r112": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r113": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 5.CC)",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=27011434&loc=d3e125687-122742",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r114": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r115": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB TOPIC 5.P.3)",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=115931487&loc=d3e140864-122747",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r116": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB TOPIC 5.P.4)",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r117": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "440",
   "URI": "https://asc.fasb.org/topic&trid=2144648",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r118": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "460",
   "URI": "https://asc.fasb.org/extlink&oid=124440162&loc=d3e12021-110248",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r119": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "460",
   "URI": "https://asc.fasb.org/extlink&oid=124440162&loc=d3e12053-110248",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r12": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(30))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r120": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=99376301&loc=d3e1243-112600",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r121": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123465755&loc=SL6230698-112601",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r122": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "20",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466302&loc=d3e4852-112606",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r123": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r124": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466204&loc=SL6031898-161870",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r125": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466204&loc=SL6031898-161870",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r126": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "470",
   "URI": "https://asc.fasb.org/topic&trid=2208564",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r127": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "63",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "480",
   "URI": "https://asc.fasb.org/extlink&oid=126970277&loc=d3e23176-110880",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r128": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(CFRR 211.02)",
   "Topic": "480",
   "URI": "https://asc.fasb.org/extlink&oid=122040564&loc=d3e177068-122764",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r129": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Topic": "480",
   "URI": "https://asc.fasb.org/extlink&oid=122040564&loc=d3e177068-122764",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r13": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(31))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r130": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Topic": "480",
   "URI": "https://asc.fasb.org/extlink&oid=122040564&loc=SL6540498-122764",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r131": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=65888546&loc=d3e21300-112643",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r132": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21553-112644",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r133": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r134": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r135": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21484-112644",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r136": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21488-112644",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r137": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21506-112644",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r138": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21521-112644",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r139": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21538-112644",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r14": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(32))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r140": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.3-04)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r141": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "505",
   "URI": "https://asc.fasb.org/topic&trid=2208762",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r142": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123453770&loc=d3e1703-114919",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r143": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123453770&loc=d3e1731-114919",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r144": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r145": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(f)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r146": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r147": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r148": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r149": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r15": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.19(a))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r150": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r151": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r152": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r153": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=SL79508275-113901",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r154": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 14.F)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r155": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=126964447&loc=d3e11149-113907",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r156": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=126964447&loc=d3e11178-113907",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r157": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "720",
   "URI": "https://asc.fasb.org/extlink&oid=6419918&loc=d3e35281-107843",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r158": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "730",
   "URI": "https://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r159": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123427490&loc=d3e31931-109318",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r16": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.19(b),22(b))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r160": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r161": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r162": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r163": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r164": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r165": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r166": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32559-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r167": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32559-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r168": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32632-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r169": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r17": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.19)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r170": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 6.I.7)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r171": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "05",
   "SubTopic": "10",
   "Subparagraph": "(a)-(d)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=6909625&loc=d3e227-128457",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r172": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "23",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "10",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=123586518&loc=d3e1043-128460",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r173": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r174": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r175": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=79982066&loc=d3e1486-128463",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r176": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "37",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=123455525&loc=d3e2207-128464",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r177": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=128092470&loc=d3e4845-128472",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r178": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=128092470&loc=d3e4845-128472",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r179": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=123410050&loc=d3e5263-128473",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r18": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.19-26)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r180": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=123410050&loc=d3e5333-128473",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r181": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "38",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=123410050&loc=d3e5504-128473",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r182": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "30",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r183": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "30",
   "SubTopic": "30",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=126966197&loc=d3e6578-128477",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r184": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "30",
   "SubTopic": "30",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=126966197&loc=d3e6613-128477",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r185": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "35",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=126966325&loc=d3e6819-128478",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r186": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r187": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)(4)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r188": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(d)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r189": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "805",
   "URI": "https://asc.fasb.org/topic&trid=2303972",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r19": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.20)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r190": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "19",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=126929396&loc=SL4569616-111683",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r191": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=109239629&loc=d3e5614-111684",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r192": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c),(3)",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r193": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r194": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r195": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5624163-113959",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r196": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5624163-113959",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r197": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4C",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r198": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4D",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5624177-113959",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r199": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126731327&loc=d3e90193-114008",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r2": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(20))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r20": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.21)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r200": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126731327&loc=d3e90198-114008",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r201": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126731327&loc=d3e90205-114008",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r202": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "820",
   "URI": "https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r203": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "820",
   "URI": "https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r204": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "820",
   "URI": "https://asc.fasb.org/extlink&oid=126976982&loc=d3e19279-110258",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r205": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=123594938&loc=d3e13467-108611",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r206": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=123594938&loc=d3e13476-108611",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r207": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=123594938&loc=d3e13531-108611",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r208": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "21",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=123594938&loc=d3e13537-108611",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r209": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "230",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=123444420&loc=d3e33268-110906",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r21": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.22(a)(1))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r210": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "https://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r211": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "https://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r212": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "https://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r213": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "https://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r214": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "20",
   "Topic": "940",
   "URI": "https://asc.fasb.org/extlink&oid=126941158&loc=d3e41242-110953",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r215": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(1)(a))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r216": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(11))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r217": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(13))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r218": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(15)(1))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r219": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(15)(2))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r22": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.22(a)(5))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r220": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(15))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r221": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(16))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r222": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(23))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r223": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03.10)",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r224": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03.15(5))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r225": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03.17)",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r226": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04(15))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r227": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04(22))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r228": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04.9)",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r229": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "470",
   "Subparagraph": "(a)",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r23": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.22)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r230": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "470",
   "Subparagraph": "(c)",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r231": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "470",
   "Subparagraph": "e",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r232": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "470",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r233": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(10))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r234": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(15)(b)(2))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r235": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(16))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r236": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(5)(c))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r237": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(12))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r238": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(15)(b)(1))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r239": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(15))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r24": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.24)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r240": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(2))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r241": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(23)(a)(4))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r242": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(25))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r243": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(8))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r244": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03.(a),19)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r245": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03.15(a))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r246": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03.5(c))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r247": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(18))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r248": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(8))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r249": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "985",
   "URI": "https://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r25": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.25)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r250": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "105",
   "URI": "https://asc.fasb.org/extlink&oid=126987489&loc=SL124442142-165695",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r251": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "105",
   "URI": "https://asc.fasb.org/extlink&oid=126987489&loc=SL124442142-165695",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r252": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "105",
   "URI": "https://asc.fasb.org/extlink&oid=126987489&loc=SL124442142-165695",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r253": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "105",
   "URI": "https://asc.fasb.org/extlink&oid=126987489&loc=SL124442142-165695",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r254": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "105",
   "URI": "https://asc.fasb.org/extlink&oid=126987489&loc=SL124442142-165695",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r255": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "205",
   "URI": "https://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r256": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "205",
   "URI": "https://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r257": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r258": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=124098289&loc=d3e6904-107765",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r259": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(1))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r26": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.29)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r260": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(13))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r261": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(14))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r262": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(15))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r263": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(16))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r264": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(17))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r265": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(18))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r266": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(27)(b))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r267": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(28))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r268": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(29))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r269": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(30)(a)(4))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r27": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.29-31)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r270": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(4))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r271": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(9))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r272": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.22(a)(2))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r273": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669619-108580",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r274": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669619-108580",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r275": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669619-108580",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r276": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669625-108580",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r277": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669625-108580",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r278": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=124431353&loc=SL116659661-227067",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r279": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=124431353&loc=SL124442407-227067",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r28": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.3,4)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r280": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=124431353&loc=SL124442411-227067",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r281": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=124431353&loc=SL124452729-227067",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r282": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(210.5-03(11))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r283": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(21))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r284": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(24))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r285": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(25))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r286": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(5))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r287": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r288": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3367-108585",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r289": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3000-108585",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r29": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669646-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r290": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "24",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3521-108585",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r291": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3536-108585",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r292": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126999549&loc=d3e4297-108586",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r293": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=126899994&loc=d3e18726-107790",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r294": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(c))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r295": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(e)(1))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r296": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(g)(1)(ii))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r297": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(h)(1))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r298": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(h)(2))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r299": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(h))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r3": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(22))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r30": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a),(b),(c)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669646-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r300": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-04(a))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24072-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r301": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column B))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r302": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column C(1)))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r303": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column C(2)))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r304": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column C)(1))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r305": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column C)(2))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r306": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column D))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r307": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column E))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r308": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "23",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124436220&loc=d3e21914-107793",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r309": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "24",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124436220&loc=d3e21930-107793",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r31": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(i),(j),(k)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669646-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r310": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124436220&loc=d3e21711-107793",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r311": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124436220&loc=d3e21728-107793",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r312": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r313": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)(2)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r314": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)(3)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r315": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)(4)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r316": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r317": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r318": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r319": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22583-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r32": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(i-k)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669646-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r320": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22595-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r321": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22644-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r322": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22644-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r323": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22658-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r324": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22663-107794",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r325": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=122038215&loc=d3e31010-122693",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r326": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 11.M.Q2)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=122038215&loc=d3e31137-122693",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r327": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1448-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r328": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "16",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1505-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r329": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1252-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r33": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669646-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r330": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1707-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r331": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "23",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1757-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r332": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1500-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r333": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1278-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r334": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "40",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)(1)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1930-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r335": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "60B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=SL5780133-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r336": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "60B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=SL5780133-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r337": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e1337-109256",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r338": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r339": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r34": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=d3e637-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r340": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=124432515&loc=d3e3630-109257",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r341": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=109243012&loc=SL65017193-207537",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r342": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=128363288&loc=d3e3842-109258",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r343": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "260",
   "URI": "https://asc.fasb.org/topic&trid=2144383",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r344": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "272",
   "URI": "https://asc.fasb.org/extlink&oid=125520817&loc=d3e70191-108054",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r345": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "272",
   "URI": "https://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r346": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "272",
   "URI": "https://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r347": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r348": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r349": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r35": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=d3e640-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r350": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6161-108592",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r351": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6191-108592",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r352": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "275",
   "URI": "https://asc.fasb.org/topic&trid=2134479",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r353": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8657-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r354": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "21",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8721-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r355": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "21",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8721-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r356": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r357": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r358": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r359": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r36": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=d3e681-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r360": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r361": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r362": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r363": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r364": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(j)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r365": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r366": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8813-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r367": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8813-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r368": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "26",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8844-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r369": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "30",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r37": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=SL7669686-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r370": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "30",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r371": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "30",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r372": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "30",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r373": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "31",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8924-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r374": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "32",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r375": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "32",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r376": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "32",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r377": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "32",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r378": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "32",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r379": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "32",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r38": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126968391&loc=d3e557-108580",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r380": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "34",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8981-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r381": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "40",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e9031-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r382": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "41",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r383": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "41",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r384": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "41",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r385": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "42",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e9054-108599",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r386": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "280",
   "URI": "https://asc.fasb.org/topic&trid=2134510",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r387": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r388": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "https://asc.fasb.org/extlink&oid=124259787&loc=d3e4531-111522",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r389": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "https://asc.fasb.org/extlink&oid=123577603&loc=d3e5074-111524",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r39": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=124507222&loc=d3e1436-108581",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r390": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "310",
   "URI": "https://asc.fasb.org/extlink&oid=126986314&loc=SL124402458-218513",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r391": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "310",
   "URI": "https://asc.fasb.org/extlink&oid=126986314&loc=SL124402458-218513",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r392": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(d)(1)",
   "Topic": "310",
   "URI": "https://asc.fasb.org/extlink&oid=126986314&loc=SL124402458-218513",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r393": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "323",
   "URI": "https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r394": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "323",
   "URI": "https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r395": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL120254519-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r396": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL120320025-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r397": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL120320025-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r398": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r399": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r4": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(24))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r40": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(1))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r400": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r401": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r402": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)(1)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r403": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)(3)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r404": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)(4)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=122640432&loc=SL121648383-210437",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r405": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r406": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r407": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Subparagraph": "(b)",
   "Topic": "340",
   "URI": "https://asc.fasb.org/extlink&oid=126905575&loc=SL49131251-203054",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r408": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Subparagraph": "(a)",
   "Topic": "340",
   "URI": "https://asc.fasb.org/extlink&oid=126905575&loc=SL49131252-203054",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r409": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r41": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(10))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r410": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r411": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r412": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r413": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r414": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(e)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r415": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(f)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r416": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r417": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(h)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r418": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r419": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r42": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(20))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r420": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r421": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(d)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r422": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(1)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r423": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r424": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(d)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r425": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r426": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)",
   "Topic": "360",
   "URI": "https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r427": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r428": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r429": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 5.P.3)",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=115931487&loc=d3e140864-122747",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r43": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(4))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r430": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 5.P.4(b)(1))",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r431": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 5.P.4(d))",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r432": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "440",
   "URI": "https://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r433": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "440",
   "URI": "https://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r434": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r435": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r436": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r437": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "20",
   "Subparagraph": "(SAB Topic 5.Y.Q2)",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r438": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "20",
   "Subparagraph": "(SAB Topic 5.Y.Q4)",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r439": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-01(a)(4)(i))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r44": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.1)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r440": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-01(a)(4)(iii)(A))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r441": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-01(a)(4)(iv))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r442": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-01(a)(5))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r443": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-02(a)(4)(i))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r444": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-02(a)(4)(iii)(A))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r445": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-02(a)(4)(iii)(B))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r446": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-02(a)(4)(iv))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r447": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-02(a)(5))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r448": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r449": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r45": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.1,2)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r450": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r451": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(e)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r452": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(f)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r453": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r454": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(h)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r455": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(i)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r456": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r457": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1C",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r458": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1C",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r459": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1C",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r46": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.2(a),(d))",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r460": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1D",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r461": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1D",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r462": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1D",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r463": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1E",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r464": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1E",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r465": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1E",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r466": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1E",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r467": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1F",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495355-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r468": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1F",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495355-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r469": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1F",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)(1)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495355-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r47": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.3)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r470": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1F",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)(2)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495355-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r471": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1I",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r472": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1I",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r473": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1I",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r474": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1I",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r475": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)(1)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r476": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466204&loc=SL6036836-161870",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r477": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r478": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r479": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r48": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.4)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r480": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r481": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r482": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(i)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r483": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r484": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r485": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r486": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r487": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "16",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496180-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r488": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r489": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r49": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.7)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r490": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r491": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r492": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r493": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.3-04)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r494": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126919976&loc=SL49130531-203044",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r495": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126919976&loc=SL49130532-203044",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r496": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126919976&loc=SL49130533-203044",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r497": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130551-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r498": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r499": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r5": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(26)(a))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r50": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.8)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r500": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r501": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r502": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r503": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130556-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r504": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)(1)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130556-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r505": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)(2)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130556-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r506": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130558-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r507": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130561-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r508": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130563-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r509": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130563-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r51": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.9)",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r510": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "19",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130564-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r511": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130566-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r512": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130566-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r513": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130566-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r514": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130566-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r515": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130543-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r516": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130545-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r517": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130549-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r518": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130549-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r519": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130550-203045",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r52": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "8",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r520": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "606",
   "URI": "https://asc.fasb.org/topic&trid=49130388",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r521": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r522": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)(6)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r523": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)(i)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r524": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)(iii)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r525": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)(iv)(03)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r526": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(e)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r527": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(f)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r528": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(h)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r529": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(l)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r53": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "220",
   "URI": "https://asc.fasb.org/topic&trid=2134417",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r530": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(o)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r531": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(p)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r532": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(q)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r533": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(r)(1)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r534": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(r)(2)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r535": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r536": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "20",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=21916913&loc=d3e273930-122802",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r537": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "60",
   "Subparagraph": "(c)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=6414203&loc=d3e39689-114964",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r538": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "60",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r539": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "70",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r54": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3213-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r540": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "80",
   "Subparagraph": "(d)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r541": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "715",
   "URI": "https://asc.fasb.org/topic&trid=2235017",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r542": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1D",
   "Publisher": "FASB",
   "Section": "35",
   "SubTopic": "10",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=126961718&loc=SL116886442-113899",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r543": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "35",
   "SubTopic": "10",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=126961718&loc=d3e4534-113899",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r544": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "35",
   "SubTopic": "10",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=126961718&loc=d3e4549-113899",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r545": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=126962052&loc=d3e4991-113900",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r546": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r547": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r548": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r549": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(3)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r55": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3213-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r550": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r551": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r552": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(ii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r553": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r554": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r555": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(01)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r556": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(02)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r557": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(03)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r558": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(04)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r559": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r56": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r560": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(ii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r561": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r562": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(01)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r563": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(02)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r564": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(03)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r565": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r566": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r567": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r568": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r569": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r57": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r570": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r571": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r572": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(ii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r573": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(iii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r574": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(iv)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r575": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(v)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r576": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)(1)(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r577": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r578": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)(2)(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r579": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r58": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r580": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(l)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r581": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128097895&loc=SL121327923-165333",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r582": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(f)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128097895&loc=SL121327923-165333",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r583": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128097895&loc=SL121327923-165333",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r584": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 14.D.2.Q6)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r585": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "718",
   "URI": "https://asc.fasb.org/topic&trid=2228938",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r586": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "35",
   "Subparagraph": "(a)",
   "Topic": "720",
   "URI": "https://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r587": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "35",
   "Subparagraph": "(b)",
   "Topic": "720",
   "URI": "https://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r588": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123427490&loc=SL37586934-109318",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r589": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123427490&loc=d3e32247-109318",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r59": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r590": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123427490&loc=d3e32280-109318",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r591": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123427490&loc=d3e31917-109318",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r592": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123427490&loc=d3e31931-109318",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r593": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32672-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r594": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r595": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r596": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r597": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r598": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(1)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r599": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(4)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r6": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(26)(b))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r60": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r600": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r601": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r602": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "19",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32840-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r603": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r604": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r605": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r606": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32847-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r607": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "21",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r608": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r609": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r61": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "24",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3521-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r610": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r611": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=126983759&loc=SL121830611-158277",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r612": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=126983759&loc=SL121830611-158277",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r613": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(d)(2)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=126983759&loc=SL121830611-158277",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r614": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(d)(3)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=126983759&loc=SL121830611-158277",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r615": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)(3)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=126983759&loc=SL121830611-158277",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r616": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB TOPIC 6.I.5.Q1)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r617": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB TOPIC 6.I.7)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r618": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 6.I.Fact.1)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r619": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 6.I.Fact.2)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r62": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(f)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3536-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r620": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 6.I.Fact.3)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r621": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 6.I.Fact.4)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r622": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 11.C)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r623": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123586238&loc=d3e39076-109324",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r624": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123586238&loc=d3e38679-109324",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r625": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=123586238&loc=d3e38679-109324",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r626": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "270",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r627": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r628": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "740",
   "URI": "https://asc.fasb.org/topic&trid=2144680",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r629": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=128092470&loc=d3e4946-128472",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r63": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3536-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r630": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=128092470&loc=d3e4946-128472",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r631": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=128092918&loc=SL128093175-196984",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r632": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=128092918&loc=SL128093175-196984",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r633": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=128092918&loc=SL128093175-196984",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r634": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)(1)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r635": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(c)(1)",
   "Topic": "805",
   "URI": "https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r636": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "19",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=126929396&loc=SL4569616-111683",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r637": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=116870748&loc=SL6758485-165988",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r638": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=116870748&loc=SL6758485-165988",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r639": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(1)",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r64": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r640": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r641": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(bb)",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=123419778&loc=d3e5710-111685",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r642": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=123419778&loc=d3e5710-111685",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r643": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=121483254&loc=SL120254523-199619",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r644": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Subparagraph": "(a)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126731327&loc=SL126733271-114008",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r645": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(a)(1)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r646": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(a)(2)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r647": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(a)(3)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r648": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(b)(1)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r649": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(b)(2)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r65": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r650": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(c)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r651": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(d)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r652": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(e)(2)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r653": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(e)(3)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r654": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(e)(4)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r655": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(f)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r656": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(a)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL126732908-238011",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r657": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "820",
   "URI": "https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r658": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r659": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r66": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r660": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL120254526-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r661": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL120254526-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r662": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL120254526-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r663": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL121967933-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r664": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL121967933-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r665": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL121967933-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r666": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL121967933-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r667": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL122642865-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r668": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=126983955&loc=SL122642865-165497",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r669": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=126980362&loc=d3e28228-110885",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r67": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3044-108585",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r670": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "35",
   "SubTopic": "20",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=123602790&loc=d3e30226-110892",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r671": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=125521441&loc=d3e30690-110894",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r672": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=125521441&loc=d3e30755-110894",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r673": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=124440516&loc=d3e30840-110895",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r674": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "230",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=123444420&loc=d3e33268-110906",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r675": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=118261656&loc=d3e32136-110900",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r676": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Subparagraph": "(a)",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r677": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r678": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Subparagraph": "(c)",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r679": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Subparagraph": "(d)",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r68": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126999549&loc=d3e4297-108586",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r680": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r681": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "21",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=118261656&loc=d3e32262-110900",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r682": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=6450520&loc=d3e32583-110901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r683": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=6450520&loc=d3e32618-110901",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r684": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "830",
   "URI": "https://asc.fasb.org/topic&trid=2175825",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r685": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "832",
   "URI": "https://asc.fasb.org/extlink&oid=128342832&loc=SL128342943-244231",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r686": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "832",
   "URI": "https://asc.fasb.org/extlink&oid=128342832&loc=SL128342957-244231",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r687": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "832",
   "URI": "https://asc.fasb.org/extlink&oid=128342835&loc=SL128342857-244232",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r688": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "832",
   "URI": "https://asc.fasb.org/extlink&oid=128342835&loc=SL128342857-244232",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r689": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "835",
   "URI": "https://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r69": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r690": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "https://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r691": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "https://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r692": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128293352&loc=SL120154346-209984",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r693": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128293352&loc=SL126838806-209984",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r694": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128293352&loc=SL126838806-209984",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r695": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128293352&loc=SL126838806-209984",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r696": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(d)(1)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128293352&loc=SL126838806-209984",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r697": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r698": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r699": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123391704&loc=SL77918631-209977",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r7": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(27)(b))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r70": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126999549&loc=d3e4313-108586",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r700": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123391704&loc=SL77918638-209977",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r701": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123391704&loc=SL77918643-209977",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r702": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123391704&loc=SL77918643-209977",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r703": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123391704&loc=SL77918643-209977",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r704": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918666-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r705": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918673-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r706": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r707": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r708": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)(1)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r709": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)(2)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r71": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126999549&loc=d3e4332-108586",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r710": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)(3)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r711": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)(4)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r712": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918701-209980",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r713": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "848",
   "URI": "https://asc.fasb.org/extlink&oid=125980421&loc=SL122150809-237846",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r714": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "848",
   "URI": "https://asc.fasb.org/extlink&oid=125980421&loc=SL125981372-237846",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r715": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)(1)",
   "Topic": "848",
   "URI": "https://asc.fasb.org/extlink&oid=125980421&loc=SL125981372-237846",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r716": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "848",
   "URI": "https://asc.fasb.org/extlink&oid=125980421&loc=SL125981372-237846",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r717": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)(3)(iii)(01)",
   "Topic": "848",
   "URI": "https://asc.fasb.org/extlink&oid=125980421&loc=SL125981372-237846",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r718": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(a)(3)(iii)(03)",
   "Topic": "848",
   "URI": "https://asc.fasb.org/extlink&oid=125980421&loc=SL125981372-237846",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r719": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "852",
   "URI": "https://asc.fasb.org/extlink&oid=124437977&loc=d3e55792-112764",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r72": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126999549&loc=SL98516268-108586",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r720": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "855",
   "URI": "https://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r721": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "855",
   "URI": "https://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r722": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "855",
   "URI": "https://asc.fasb.org/topic&trid=2122774",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r723": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)(1)",
   "Topic": "860",
   "URI": "https://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r724": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "910",
   "URI": "https://asc.fasb.org/extlink&oid=126937589&loc=SL119991595-234733",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r725": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "310",
   "Subparagraph": "(b)",
   "Topic": "912",
   "URI": "https://asc.fasb.org/extlink&oid=126938201&loc=d3e55415-109406",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r726": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 11.L)",
   "Topic": "924",
   "URI": "https://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r727": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "926",
   "URI": "https://asc.fasb.org/extlink&oid=120154696&loc=d3e54445-107959",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r728": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "926",
   "URI": "https://asc.fasb.org/extlink&oid=120154821&loc=SL120154904-197079",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r729": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "926",
   "URI": "https://asc.fasb.org/extlink&oid=120154821&loc=SL120154904-197079",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r73": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "235",
   "URI": "https://asc.fasb.org/topic&trid=2122369",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r730": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "926",
   "URI": "https://asc.fasb.org/extlink&oid=120154821&loc=SL120154904-197079",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r731": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "340",
   "Topic": "928",
   "URI": "https://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r732": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(10)(1))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r733": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04(23))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r734": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04(26))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r735": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04(27))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r736": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "235",
   "Subparagraph": "(SX 210.9-05(b)(2))",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r737": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "360",
   "Topic": "942",
   "URI": "https://asc.fasb.org/extlink&oid=124429447&loc=SL124453093-239630",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r738": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(23)(a)(3))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r739": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(19))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r74": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r740": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(22))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r741": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(23))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r742": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(9))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r743": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Subparagraph": "(d)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124506351&loc=SL117782755-158439",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r744": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(a)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r745": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(b)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r746": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(e)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r747": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(f)(1)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r748": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(f)(2)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r749": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(g)(1)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r75": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r750": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(g)(2)(i)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r751": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(g)(2)(ii)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r752": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(g)(2)(iii)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r753": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(g)(2)(iv)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r754": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(h)(1)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r755": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(h)(2)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r756": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "825",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=123600520&loc=SL75241803-196195",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r757": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "320",
   "Subparagraph": "(SX 210.12-13(Column B)(Footnote 1))",
   "Topic": "946",
   "URI": "https://asc.fasb.org/extlink&oid=122147990&loc=d3e611282-123010",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r758": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "320",
   "Subparagraph": "(SX 210.12-13(Column C)(Footnote 1))",
   "Topic": "946",
   "URI": "https://asc.fasb.org/extlink&oid=122147990&loc=d3e611282-123010",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r759": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "320",
   "Subparagraph": "(SX 210.12-13(Column D)(Footnote 1))",
   "Topic": "946",
   "URI": "https://asc.fasb.org/extlink&oid=122147990&loc=d3e611282-123010",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r76": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "52",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=128363288&loc=d3e4984-109258",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r760": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "320",
   "Subparagraph": "(SX 210.12-13(Column E)(Footnote 1))",
   "Topic": "946",
   "URI": "https://asc.fasb.org/extlink&oid=122147990&loc=d3e611282-123010",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r761": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "320",
   "Subparagraph": "(SX 210.12-13(Column F)(Footnote 1))",
   "Topic": "946",
   "URI": "https://asc.fasb.org/extlink&oid=122147990&loc=d3e611282-123010",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r762": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "320",
   "Subparagraph": "(SX 210.12-13(Column G)(Footnote 1))",
   "Topic": "946",
   "URI": "https://asc.fasb.org/extlink&oid=122147990&loc=d3e611282-123010",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r763": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "310",
   "Subparagraph": "(SX 210.12-29(Footnote 4))",
   "Topic": "948",
   "URI": "https://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r764": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "210",
   "Topic": "954",
   "URI": "https://asc.fasb.org/extlink&oid=120413173&loc=SL116631458-115580",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r765": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "310",
   "Topic": "954",
   "URI": "https://asc.fasb.org/extlink&oid=126942805&loc=d3e3115-115594",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r766": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "440",
   "Subparagraph": "(a)",
   "Topic": "954",
   "URI": "https://asc.fasb.org/extlink&oid=6491277&loc=d3e6429-115629",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r767": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "440",
   "Subparagraph": "(d)",
   "Topic": "954",
   "URI": "https://asc.fasb.org/extlink&oid=6491277&loc=d3e6429-115629",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r768": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "360",
   "Subparagraph": "(d)",
   "Topic": "958",
   "URI": "https://asc.fasb.org/extlink&oid=126982197&loc=d3e99779-112916",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r769": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "360",
   "Topic": "958",
   "URI": "https://asc.fasb.org/extlink&oid=126982197&loc=d3e99893-112916",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r77": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r770": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Column B))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r771": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Column C))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r772": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Column D))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r773": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Column E))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r774": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Column F))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r775": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Column G))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r776": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Column H))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r777": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Column I))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r778": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Footnote 2))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r779": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Footnote 4))",
   "Topic": "970",
   "URI": "https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r78": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r780": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "310",
   "Subparagraph": "(c)",
   "Topic": "976",
   "URI": "https://asc.fasb.org/extlink&oid=6497875&loc=d3e22274-108663",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r781": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "310",
   "Subparagraph": "(b)",
   "Topic": "978",
   "URI": "https://asc.fasb.org/extlink&oid=126945304&loc=d3e27327-108691",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r782": {
   "Name": "Regulation S-K (SK)",
   "Number": "229",
   "Paragraph": "(a)",
   "Publisher": "SEC",
   "Section": "1402",
   "role": "http://www.xbrl.org/2003/role/disclosureRef"
  },
  "r783": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r784": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=124098289&loc=d3e6935-107765",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r785": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r786": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=126899994&loc=d3e18823-107790",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r787": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=126899994&loc=d3e18823-107790",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r788": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "52",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=128363288&loc=d3e4984-109258",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r789": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "30",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r79": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r790": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "31",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8924-108599",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r791": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "24",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=122137925&loc=d3e14258-109268",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r792": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r793": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "69B",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r794": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "69C",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r795": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "69E",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466577&loc=SL123495743-112612",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r796": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "69F",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466577&loc=SL123495745-112612",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r797": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "505",
   "URI": "https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r798": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130690-203046-203046",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r799": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130690-203046-203046",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r8": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(28))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r80": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6061-108592",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r800": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130690-203046-203046",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r801": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130690-203046-203046",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r802": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130690-203046-203046",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r803": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(f)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130690-203046-203046",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r804": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130690-203046-203046",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r805": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)(ii)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r806": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r807": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r808": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "80",
   "Subparagraph": "(a)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r809": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "80",
   "Subparagraph": "(a)",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=65877416&loc=SL14450673-114947",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r81": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6132-108592",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r810": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "80",
   "Topic": "715",
   "URI": "https://asc.fasb.org/extlink&oid=35742348&loc=SL14450788-114948",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r811": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r812": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r813": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(3)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r814": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "217",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=126976462&loc=d3e36027-109320",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r815": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4J",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=120409616&loc=SL4591551-111686",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r816": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4K",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "https://asc.fasb.org/extlink&oid=120409616&loc=SL4591552-111686",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r817": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4D",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5624177-113959",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r818": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "53",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r819": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "852",
   "URI": "https://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r82": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6143-108592",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r820": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13H",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "40",
   "Subparagraph": "(a)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126561865&loc=SL117783719-158441",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r821": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13H",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "40",
   "Subparagraph": "(b)",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126561865&loc=SL117783719-158441",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r822": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "29F",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "40",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=126561865&loc=SL117819544-158441",
   "role": "http://www.xbrl.org/2003/role/exampleRef"
  },
  "r823": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "b",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r824": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "b-2",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r825": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "b-23",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r826": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "d1-1",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r827": {
   "Name": "Form 10-K",
   "Number": "249",
   "Publisher": "SEC",
   "Section": "310",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r828": {
   "Name": "Form 20-F",
   "Number": "249",
   "Publisher": "SEC",
   "Section": "220",
   "Subsection": "f",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r829": {
   "Name": "Form 40-F",
   "Number": "249",
   "Publisher": "SEC",
   "Section": "240",
   "Subsection": "f",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r83": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r830": {
   "Name": "Forms 10-K, 10-Q, 20-F",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "13",
   "Subsection": "a-1",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r831": {
   "Name": "Regulation S-T",
   "Number": "232",
   "Publisher": "SEC",
   "Section": "405",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r832": {
   "Name": "Securities Act",
   "Number": "230",
   "Publisher": "SEC",
   "Section": "405",
   "role": "http://www.xbrl.org/2003/role/presentationRef"
  },
  "r833": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "272",
   "URI": "https://asc.fasb.org/extlink&oid=125520817&loc=d3e70229-108054",
   "role": "http://www.xbrl.org/2003/role/recommendedDisclosureRef"
  },
  "r834": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(17))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r835": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(3)(a)(4))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r836": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(9))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r837": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=124431353&loc=SL124442407-227067",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r838": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=124431353&loc=SL124442411-227067",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r839": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "https://asc.fasb.org/extlink&oid=124431353&loc=SL124452729-227067",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r84": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8813-108599",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r840": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r841": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3213-108585",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r842": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r843": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r844": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r845": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r846": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(d))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r847": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(f))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r848": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(g)(1)(ii))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r849": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(h)(1)(Note 1))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r85": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "30",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r850": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column B))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r851": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column C(1)))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r852": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column C(2)))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r853": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column D))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r854": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-09(Column E))",
   "Topic": "235",
   "URI": "https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r855": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "23",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124436220&loc=d3e21914-107793",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r856": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "24",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124436220&loc=d3e21930-107793",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r857": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124436220&loc=d3e21711-107793",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r858": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r859": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "https://asc.fasb.org/extlink&oid=124431687&loc=d3e22583-107794",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r86": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "30",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r860": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "55",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=126958026&loc=d3e2626-109256",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r861": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "260",
   "URI": "https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r862": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "https://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r863": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8672-108599",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r864": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "323",
   "URI": "https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r865": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "326",
   "URI": "https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r866": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Subparagraph": "(b)",
   "Topic": "340",
   "URI": "https://asc.fasb.org/extlink&oid=126905575&loc=SL49131251-203054",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r867": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r868": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r869": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r87": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "31",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e8924-108599",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r870": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r871": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(e)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r872": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(f)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r873": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r874": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(h)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r875": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r876": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=SL108378252-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r877": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13854-109267",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r878": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r879": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(c)",
   "Topic": "410",
   "URI": "https://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r88": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "41",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r880": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "420",
   "URI": "https://asc.fasb.org/extlink&oid=109237686&loc=d3e17752-110868",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r881": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "440",
   "URI": "https://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r882": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r883": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r884": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r885": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r886": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "20",
   "Subparagraph": "(SAB Topic 5.Y.Q2)",
   "Topic": "450",
   "URI": "https://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r887": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "450",
   "URI": "https://asc.fasb.org/topic&trid=2127136",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r888": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-01(a)(4)(i))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r889": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-01(a)(4)(ii))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r89": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "https://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r890": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-01(a)(4)(iii))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r891": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-01(a)(4)(iv))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r892": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.13-02(a)(4)(iv))",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r893": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r894": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1D",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r895": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)(1)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130556-203045",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r896": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920106&loc=SL49130545-203045",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r897": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "27",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130611-203046-203046",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r898": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "https://asc.fasb.org/extlink&oid=126920602&loc=SL49130690-203046-203046",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r899": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r9": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(29))",
   "Topic": "210",
   "URI": "https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r90": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 4.E)",
   "Topic": "310",
   "URI": "https://asc.fasb.org/extlink&oid=122038336&loc=d3e74512-122707",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r900": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r901": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(3)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r902": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r903": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(ii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r904": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r905": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r906": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(01)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r907": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(02)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r908": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(03)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r909": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(04)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r91": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r910": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r911": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(ii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r912": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r913": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(01)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r914": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(02)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r915": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(03)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r916": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r917": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r918": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)(1)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r919": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)(2)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r92": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r920": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(i)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r921": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(ii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r922": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(iii)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r923": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(iv)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r924": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(v)",
   "Topic": "718",
   "URI": "https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r925": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r926": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r927": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r928": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32621-109319",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r929": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r93": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r930": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r931": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 6.I.7)",
   "Topic": "740",
   "URI": "https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r932": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "808",
   "URI": "https://asc.fasb.org/extlink&oid=6931272&loc=SL5834143-161434",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r933": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r934": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r935": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6A",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "20",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=124256753&loc=SL5864739-113975",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r936": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "40",
   "Subparagraph": "(e)(3)",
   "Topic": "815",
   "URI": "https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r937": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(bbb)(2)",
   "Topic": "820",
   "URI": "https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r938": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)",
   "Topic": "825",
   "URI": "https://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r939": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r94": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r940": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "830",
   "URI": "https://asc.fasb.org/extlink&oid=6450520&loc=d3e32583-110901",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r941": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=123391704&loc=SL77918638-209977",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r942": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)(3)",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918673-209980",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r943": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r944": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "https://asc.fasb.org/extlink&oid=128292326&loc=SL77918701-209980",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r945": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "852",
   "URI": "https://asc.fasb.org/extlink&oid=124433192&loc=SL2890621-112765",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r946": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "852",
   "URI": "https://asc.fasb.org/extlink&oid=124433192&loc=SL2890621-112765",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r947": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)(1)",
   "Topic": "860",
   "URI": "https://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r948": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)(2)",
   "Topic": "860",
   "URI": "https://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r949": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(c)(3)",
   "Topic": "860",
   "URI": "https://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r95": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(3)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r950": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)(1)",
   "Topic": "860",
   "URI": "https://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r951": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)(2)",
   "Topic": "860",
   "URI": "https://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r952": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)(3)",
   "Topic": "860",
   "URI": "https://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r953": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "730",
   "Topic": "912",
   "URI": "https://asc.fasb.org/extlink&oid=6472174&loc=d3e58812-109433",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r954": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(3)(b))",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r955": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4H",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=116884468&loc=SL65671331-158438",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r956": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "825",
   "Topic": "944",
   "URI": "https://asc.fasb.org/extlink&oid=123600520&loc=SL75241803-196195",
   "role": "http://www.xbrl.org/2009/role/commonPracticeRef"
  },
  "r96": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r97": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "((a)(1),(b))",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r98": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  },
  "r99": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(1)",
   "Topic": "350",
   "URI": "https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275",
   "role": "http://fasb.org/us-gaap/role/ref/legacyRef"
  }
 },
 "version": "2.2"
}
