{
 "instance": {
  "fivn-20191231.htm": {
   "axisCustom": 3,
   "axisStandard": 34,
   "contextCount": 300,
   "dts": {
    "calculationLink": {
     "local": [
      "fivn-20191231_cal.xml"
     ]
    },
    "definitionLink": {
     "local": [
      "fivn-20191231_def.xml"
     ],
     "remote": [
      "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-eedm-def-2019-01-31.xml",
      "http://xbrl.fasb.org/srt/2019/elts/srt-eedm1-def-2019-01-31.xml"
     ]
    },
    "inline": {
     "local": [
      "fivn-20191231.htm"
     ]
    },
    "labelLink": {
     "local": [
      "fivn-20191231_lab.xml"
     ],
     "remote": [
      "http://xbrl.fasb.org/srt/2019/elts/srt-doc-2019-01-31.xml",
      "https://xbrl.sec.gov/dei/2019/dei-doc-2019-01-31.xml",
      "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-doc-2019-01-31.xml"
     ]
    },
    "presentationLink": {
     "local": [
      "fivn-20191231_pre.xml"
     ]
    },
    "referenceLink": {
     "remote": [
      "https://xbrl.sec.gov/dei/2019/dei-ref-2019-01-31.xml",
      "http://xbrl.fasb.org/srt/2019/elts/srt-ref-2019-01-31.xml",
      "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-ref-2019-01-31.xml"
     ]
    },
    "schema": {
     "local": [
      "fivn-20191231.xsd"
     ],
     "remote": [
      "http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd",
      "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/dtr/type/numeric-2009-12-16.xsd",
      "http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd",
      "http://www.xbrl.org/2005/xbrldt-2005.xsd",
      "http://www.xbrl.org/2006/ref-2006-02-27.xsd",
      "http://xbrl.fasb.org/srt/2019/elts/srt-types-2019-01-31.xsd",
      "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd",
      "http://xbrl.fasb.org/us-gaap/2019/elts/us-roles-2019-01-31.xsd",
      "http://xbrl.fasb.org/srt/2019/elts/srt-roles-2019-01-31.xsd",
      "https://xbrl.sec.gov/country/2017/country-2017-01-31.xsd",
      "http://xbrl.fasb.org/us-gaap/2019/elts/us-types-2019-01-31.xsd",
      "https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd",
      "http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd",
      "http://www.xbrl.org/lrr/role/net-2009-12-16.xsd",
      "http://www.xbrl.org/lrr/role/deprecated-2009-12-16.xsd",
      "http://www.xbrl.org/lrr/role/reference-2009-12-16.xsd",
      "http://xbrl.fasb.org/us-gaap/2019/elts/us-parts-codification-2019-01-31.xsd"
     ]
    }
   },
   "elementCount": 706,
   "entityCount": 1,
   "hidden": {
    "http://fasb.org/us-gaap/2019-01-31": 19,
    "http://www.five9.com/20191231": 1,
    "http://xbrl.sec.gov/dei/2019-01-31": 6,
    "total": 26
   },
   "keyCustom": 47,
   "keyStandard": 461,
   "memberCustom": 23,
   "memberStandard": 59,
   "nsprefix": "fivn",
   "nsuri": "http://www.five9.com/20191231",
   "report": {
    "R1": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "dei:DocumentType",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "document",
     "isDefault": "true",
     "longName": "0001001 - Document - Cover Page",
     "role": "http://www.five9.com/role/CoverPage",
     "shortName": "Cover Page",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "dei:DocumentType",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R10": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "fivn:InvestmentsAndFairValueMeasurementsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2115103 - Disclosure - Investments and Fair Value Measurements",
     "role": "http://www.five9.com/role/InvestmentsandFairValueMeasurements",
     "shortName": "Investments and Fair Value Measurements",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "fivn:InvestmentsAndFairValueMeasurementsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R100": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i9adb54f3624444f4b5c1bbfc2ae3fb8c_D20191001-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2493463 - Disclosure - Selected Quarterly Financial Data (Unaudited) - Schedule of Quarterly Financial Information (Details)",
     "role": "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails",
     "shortName": "Selected Quarterly Financial Data (Unaudited) - Schedule of Quarterly Financial Information (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i9adb54f3624444f4b5c1bbfc2ae3fb8c_D20191001-20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:CostOfRevenue",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R101": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i9adb54f3624444f4b5c1bbfc2ae3fb8c_D20191001-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensation",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2494464 - Disclosure - Selected Quarterly Financial Data (Unaudited) - Allocation of Stock-Based Compensation Expense (Details)",
     "role": "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails",
     "shortName": "Selected Quarterly Financial Data (Unaudited) - Allocation of Stock-Based Compensation Expense (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i94a3d508cb6741c3bd370042b4cc15d6_D20190701-20190930",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:ShareBasedCompensation",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R102": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i9adb54f3624444f4b5c1bbfc2ae3fb8c_D20191001-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DepreciationDepletionAndAmortization",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2495465 - Disclosure - Selected Quarterly Financial Data (Unaudited) - Allocation of Depreciation and Amortization Expense (Details)",
     "role": "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
     "shortName": "Selected Quarterly Financial Data (Unaudited) - Allocation of Depreciation and Amortization Expense (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i94a3d508cb6741c3bd370042b4cc15d6_D20190701-20190930",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:DepreciationDepletionAndAmortization",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R11": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SupplementalBalanceSheetDisclosuresTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2121104 - Disclosure - Financial Statement Components",
     "role": "http://www.five9.com/role/FinancialStatementComponents",
     "shortName": "Financial Statement Components",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SupplementalBalanceSheetDisclosuresTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R12": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2130105 - Disclosure - Goodwill and Intangible Assets",
     "role": "http://www.five9.com/role/GoodwillandIntangibleAssets",
     "shortName": "Goodwill and Intangible Assets",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R13": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DebtDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2135106 - Disclosure - Debt",
     "role": "http://www.five9.com/role/Debt",
     "shortName": "Debt",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DebtDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R14": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ShareholdersEquityAndShareBasedPaymentsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2144107 - Disclosure - Stockholders' Equity",
     "role": "http://www.five9.com/role/StockholdersEquity",
     "shortName": "Stockholders' Equity",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ShareholdersEquityAndShareBasedPaymentsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R15": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:EarningsPerShareTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2154108 - Disclosure - Net Loss Per Share",
     "role": "http://www.five9.com/role/NetLossPerShare",
     "shortName": "Net Loss Per Share",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:EarningsPerShareTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R16": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:IncomeTaxDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2159109 - Disclosure - Income Taxes",
     "role": "http://www.five9.com/role/IncomeTaxes",
     "shortName": "Income Taxes",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:IncomeTaxDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R17": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2167110 - Disclosure - Commitments and Contingencies",
     "role": "http://www.five9.com/role/CommitmentsandContingencies",
     "shortName": "Commitments and Contingencies",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R18": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SegmentReportingDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2174111 - Disclosure - Geographical Information",
     "role": "http://www.five9.com/role/GeographicalInformation",
     "shortName": "Geographical Information",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SegmentReportingDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R19": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2177112 - Disclosure - Retirement Plans",
     "role": "http://www.five9.com/role/RetirementPlans",
     "shortName": "Retirement Plans",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R2": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfCashAndCashEquivalentsTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CashAndCashEquivalentsAtCarryingValue",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "1001002 - Statement - Consolidated Balance Sheets",
     "role": "http://www.five9.com/role/ConsolidatedBalanceSheets",
     "shortName": "Consolidated Balance Sheets",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R20": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:LesseeOperatingLeasesTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2179113 - Disclosure - ASC 842 Adoption Impact",
     "role": "http://www.five9.com/role/ASC842AdoptionImpact",
     "shortName": "ASC 842 Adoption Impact",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:LesseeOperatingLeasesTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R21": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "fivn:AssetAcquisitionDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2187114 - Disclosure - Acquisition of Whendu LLC",
     "role": "http://www.five9.com/role/AcquisitionofWhenduLLC",
     "shortName": "Acquisition of Whendu LLC",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "fivn:AssetAcquisitionDisclosureTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R22": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SubsequentEventsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2189115 - Disclosure - Subsequent Events",
     "role": "http://www.five9.com/role/SubsequentEvents",
     "shortName": "Subsequent Events",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SubsequentEventsTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R23": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:QuarterlyFinancialInformationTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2191116 - Disclosure - Selected Quarterly Financial Data (Unaudited)",
     "role": "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnaudited",
     "shortName": "Selected Quarterly Financial Data (Unaudited)",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:QuarterlyFinancialInformationTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R24": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:BasisOfAccountingPolicyPolicyTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2202201 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Policies)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies",
     "shortName": "Description of Business and Summary of Significant Accounting Policies (Policies)",
     "subGroupType": "policies",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:BasisOfAccountingPolicyPolicyTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R25": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfCreditLossesForFinancingReceivablesCurrentTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2303301 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Tables)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesTables",
     "shortName": "Description of Business and Summary of Significant Accounting Policies (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfCreditLossesForFinancingReceivablesCurrentTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R26": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ContractWithCustomerAssetAndLiabilityTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2312302 - Disclosure - Revenue (Tables)",
     "role": "http://www.five9.com/role/RevenueTables",
     "shortName": "Revenue (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ContractWithCustomerAssetAndLiabilityTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R27": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DebtSecuritiesAvailableForSaleTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2316303 - Disclosure - Investments and Fair Value Measurements (Tables)",
     "role": "http://www.five9.com/role/InvestmentsandFairValueMeasurementsTables",
     "shortName": "Investments and Fair Value Measurements (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:DebtSecuritiesAvailableForSaleTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R28": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfCashAndCashEquivalentsTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2322304 - Disclosure - Financial Statement Components (Tables)",
     "role": "http://www.five9.com/role/FinancialStatementComponentsTables",
     "shortName": "Financial Statement Components (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfCashAndCashEquivalentsTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R29": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2331305 - Disclosure - Goodwill and Intangible Assets (Tables)",
     "role": "http://www.five9.com/role/GoodwillandIntangibleAssetsTables",
     "shortName": "Goodwill and Intangible Assets (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R3": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:PreferredStockParOrStatedValuePerShare",
      "reportCount": 1,
      "unitRef": "usdPerShare",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "1002003 - Statement - Consolidated Balance Sheets (Parenthetical)",
     "role": "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
     "shortName": "Consolidated Balance Sheets (Parenthetical)",
     "subGroupType": "parenthetical",
     "uniqueAnchor": null
    },
    "R30": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ConvertibleDebtTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2336306 - Disclosure - Debt (Tables)",
     "role": "http://www.five9.com/role/DebtTables",
     "shortName": "Debt (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ConvertibleDebtTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R31": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "fivn:SummaryofCommonStockReservedforFutureIssuanceTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2345307 - Disclosure - Stockholders' Equity (Tables)",
     "role": "http://www.five9.com/role/StockholdersEquityTables",
     "shortName": "Stockholders' Equity (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "fivn:SummaryofCommonStockReservedforFutureIssuanceTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R32": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2355308 - Disclosure - Net Loss Per Share (Tables)",
     "role": "http://www.five9.com/role/NetLossPerShareTables",
     "shortName": "Net Loss Per Share (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R33": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2360309 - Disclosure - Income Taxes (Tables)",
     "role": "http://www.five9.com/role/IncomeTaxesTables",
     "shortName": "Income Taxes (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R34": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "srt:ContractualObligationFiscalYearMaturityScheduleTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2368310 - Disclosure - Commitments and Contingencies (Tables)",
     "role": "http://www.five9.com/role/CommitmentsandContingenciesTables",
     "shortName": "Commitments and Contingencies (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "srt:ContractualObligationFiscalYearMaturityScheduleTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R35": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2375311 - Disclosure - Geographical Information (Tables)",
     "role": "http://www.five9.com/role/GeographicalInformationTables",
     "shortName": "Geographical Information (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R36": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:LeaseCostTableTextBlock",
      "reportCount": 1,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2380312 - Disclosure - ASC 842 Adoption Impact (Tables)",
     "role": "http://www.five9.com/role/ASC842AdoptionImpactTables",
     "shortName": "ASC 842 Adoption Impact (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "lang": "en-US",
      "name": "fivn:ScheduleOfBalanceSheetInformationRelatedtoLeasesTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R37": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2392313 - Disclosure - Selected Quarterly Financial Data (Unaudited) (Tables)",
     "role": "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedTables",
     "shortName": "Selected Quarterly Financial Data (Unaudited) (Tables)",
     "subGroupType": "tables",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R38": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:CashUninsuredAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2404401 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Concentration Risks (Details)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesConcentrationRisksDetails",
     "shortName": "Description of Business and Summary of Significant Accounting Policies - Concentration Risks (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:CashUninsuredAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R39": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfCreditLossesForFinancingReceivablesCurrentTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "idb9a47ebf5374b02b40416f6cae24e06_I20181231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AllowanceForDoubtfulAccountsReceivable",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2405402 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesAllowanceforDoubtfulAccountsDetails",
     "shortName": "Description of Business and Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfCreditLossesForFinancingReceivablesCurrentTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "lang": null,
      "name": "fivn:AllowanceForDoubtfulAccountsReceivableWriteOffsNetOfRecoveries",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R4": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "1003004 - Statement - Consolidated Statements of Operations and Comprehensive Loss",
     "role": "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
     "shortName": "Consolidated Statements of Operations and Comprehensive Loss",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:ComprehensiveIncomeNetOfTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R40": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:PropertyPlantAndEquipmentTextBlock",
       "us-gaap:PropertyPlantAndEquipmentPolicyTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ibd060c8cba7e4afcad097091a99cb7aa_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:PropertyPlantAndEquipmentUsefulLife",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2406403 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Property and Equipment, Net (Details)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
     "shortName": "Description of Business and Summary of Significant Accounting Policies - Property and Equipment, Net (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:PropertyPlantAndEquipmentTextBlock",
       "us-gaap:PropertyPlantAndEquipmentPolicyTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ibd060c8cba7e4afcad097091a99cb7aa_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:PropertyPlantAndEquipmentUsefulLife",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R41": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:FiniteLivedIntangibleAssetUsefulLife",
      "reportCount": 1,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2407404 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Goodwill and Intangible Assets (Details)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesGoodwillandIntangibleAssetsDetails",
     "shortName": "Description of Business and Summary of Significant Accounting Policies - Goodwill and Intangible Assets (Details)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R42": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:AdvertisingExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2408405 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Advertising Costs (Details)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesAdvertisingCostsDetails",
     "shortName": "Description of Business and Summary of Significant Accounting Policies - Advertising Costs (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:AdvertisingExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R43": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:SalesCommissionsAndFees",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2409406 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Commissions (Details)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesCommissionsDetails",
     "shortName": "Description of Business and Summary of Significant Accounting Policies - Commissions (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:SalesCommissionsAndFees",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R44": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DeferredTaxAssetsGross",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2410407 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Recently Adopted Accounting Pronouncements (Details)",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails",
     "shortName": "Description of Business and Summary of Significant Accounting Policies - Recently Adopted Accounting Pronouncements (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "us-gaap:NewAccountingPronouncementsPolicyPolicyTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "iec837d05a302445f8a098bc194c58581_I20170101",
      "decimals": "-5",
      "lang": null,
      "name": "us-gaap:DeferredTaxAssetsGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R45": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:ContractWithCustomerLiabilityRevenueRecognized",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2413408 - Disclosure - Revenue - Narrative (Details)",
     "role": "http://www.five9.com/role/RevenueNarrativeDetails",
     "shortName": "Revenue - Narrative (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:ContractWithCustomerLiabilityRevenueRecognized",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R46": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ContractWithCustomerAssetAndLiabilityTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AccountsReceivableNetCurrent",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2414409 - Disclosure - ASC 606 Adoption Impact and Revenue from Contracts with Customers - Contract Balances (Details)",
     "role": "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails",
     "shortName": "ASC 606 Adoption Impact and Revenue from Contracts with Customers - Contract Balances (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ContractWithCustomerAssetAndLiabilityTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "idfa902889be3464ea6f3729da484246a_I20180101",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:CapitalizedContractCostNetCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R47": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:DebtSecuritiesAvailableForSaleTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2417410 - Disclosure - Investments and Fair Value Measurements - Schedule of Marketable Investments (Details)",
     "role": "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails",
     "shortName": "Investments and Fair Value Measurements - Schedule of Marketable Investments (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:DebtSecuritiesAvailableForSaleTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R48": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:UnrealizedGainLossOnInvestmentsTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2418411 - Disclosure - Investments and Fair Value Measurements - Schedule of Continuous Unrealized Loss Position (Details)",
     "role": "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
     "shortName": "Investments and Fair Value Measurements - Schedule of Continuous Unrealized Loss Position (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:UnrealizedGainLossOnInvestmentsTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R49": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:FairValueByBalanceSheetGroupingTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CashAndCashEquivalentsFairValueDisclosure",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2419412 - Disclosure - Investments and Fair Value Measurements - Schedule of Assets Carried at Fair Value (Details)",
     "role": "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
     "shortName": "Investments and Fair Value Measurements - Schedule of Assets Carried at Fair Value (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:FairValueByBalanceSheetGroupingTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CashAndCashEquivalentsFairValueDisclosure",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R5": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ic142f19fbd6b434bb681b5efb7687509_I20161231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:SharesIssued",
      "reportCount": 1,
      "unique": true,
      "unitRef": "shares",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "1004005 - Statement - Consolidated Statements of Stockholders' Equity",
     "role": "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
     "shortName": "Consolidated Statements of Stockholders' Equity",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ic142f19fbd6b434bb681b5efb7687509_I20161231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:SharesIssued",
      "reportCount": 1,
      "unique": true,
      "unitRef": "shares",
      "xsiNil": "false"
     }
    },
    "R50": {
     "firstAnchor": {
      "ancestors": [
       "us-gaap:AssetsFairValueDisclosure",
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i6340e9152d6d484e886230ddf2c3d285_I20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:AssetsFairValueDisclosure",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2420413 - Disclosure - Investments and Fair Value Measurements - Narrative (Details)",
     "role": "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
     "shortName": "Investments and Fair Value Measurements - Narrative (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "us-gaap:AssetsFairValueDisclosure",
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i6340e9152d6d484e886230ddf2c3d285_I20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:AssetsFairValueDisclosure",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R51": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfCashAndCashEquivalentsTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CashAndCashEquivalentsAtCarryingValue",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2423414 - Disclosure - Financial Statement Components - Schedule of Cash and Cash Equivalents (Details)",
     "role": "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails",
     "shortName": "Financial Statement Components - Schedule of Cash and Cash Equivalents (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfCashAndCashEquivalentsTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i8d3445fe9e114e808270beeb5356787b_I20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:CashAndCashEquivalentsAtCarryingValue",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R52": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AllowanceForDoubtfulAccountsReceivable",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2424415 - Disclosure - Financial Statement Components - Schedule of Accounts Receivable (Details)",
     "role": "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails",
     "shortName": "Financial Statement Components - Schedule of Accounts Receivable (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i51107b1a97ae4b63b7b1167731c9a07b_I20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:AccountsReceivableGrossCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R53": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PrepaidExpenseCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2425416 - Disclosure - Financial Statement Components - Schedule of Prepaid Expenses and Other Current Assets (Details)",
     "role": "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails",
     "shortName": "Financial Statement Components - Schedule of Prepaid Expenses and Other Current Assets (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PrepaidExpenseCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R54": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PropertyPlantAndEquipmentGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2426417 - Disclosure - Financial Statement Components - Schedule of Property and Equipment (Details)",
     "role": "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails",
     "shortName": "Financial Statement Components - Schedule of Property and Equipment (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PropertyPlantAndEquipmentGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R55": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:Depreciation",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2427418 - Disclosure - Financial Statement Components - Narrative (Details)",
     "role": "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails",
     "shortName": "Financial Statement Components - Narrative (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:Depreciation",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R56": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "fivn:ScheduleOfBalanceSheetInformationRelatedtoLeasesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "fivn:FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2428419 - Disclosure - Financial Statement Components - Schedule of Capital Leased Property and Equipment (Details)",
     "role": "http://www.five9.com/role/FinancialStatementComponentsScheduleofCapitalLeasedPropertyandEquipmentDetails",
     "shortName": "Financial Statement Components - Schedule of Capital Leased Property and Equipment (Details)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R57": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:OtherCurrentLiabilitiesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AccruedLiabilitiesCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2429420 - Disclosure - Financial Statement Components - Schedule of Accrued and Other Current Liabilities (Details)",
     "role": "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccruedandOtherCurrentLiabilitiesDetails",
     "shortName": "Financial Statement Components - Schedule of Accrued and Other Current Liabilities (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:OtherCurrentLiabilitiesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AccruedLiabilitiesCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R58": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:GoodwillImpairedAccumulatedImpairmentLoss",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2432421 - Disclosure - Goodwill and Intangible Assets - Narrative (Details)",
     "role": "http://www.five9.com/role/GoodwillandIntangibleAssetsNarrativeDetails",
     "shortName": "Goodwill and Intangible Assets - Narrative (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:GoodwillImpairedAccumulatedImpairmentLoss",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R59": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:FiniteLivedIntangibleAssetsGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2433422 - Disclosure - Goodwill and Intangible Assets - Schedule of Intangible Assets (Details)",
     "role": "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails",
     "shortName": "Goodwill and Intangible Assets - Schedule of Intangible Assets (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:FiniteLivedIntangibleAssetsGross",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R6": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:NetIncomeLoss",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "1005006 - Statement - Consolidated Statements of Cash Flows",
     "role": "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
     "shortName": "Consolidated Statements of Cash Flows",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "lang": null,
      "name": "fivn:AmortizationOfOperatingLeaseRightOfUseAssets",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R60": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2434423 - Disclosure - Goodwill and Intangible Assets - Schedule of Expected Future Amortization Expense of Intangible Assets (Details)",
     "role": "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails",
     "shortName": "Goodwill and Intangible Assets - Schedule of Expected Future Amortization Expense of Intangible Assets (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R61": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i0d20343dd83e4149b34b0d37aec4ddcd_D20180101-20181231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PaymentsOfDebtIssuanceCosts",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2437424 - Disclosure - Debt - Convertible Senior Notes and Capped Call (Details)",
     "role": "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
     "shortName": "Debt - Convertible Senior Notes and Capped Call (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ica43e9b561664c8b97744c7ae7c967ed_D20180501-20180531",
      "decimals": "-5",
      "lang": null,
      "name": "us-gaap:ProceedsFromIssuanceOfDebt",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R62": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DebtInstrumentCarryingAmount",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2438425 - Disclosure - Debt - Schedule of Net Carrying Amount of the Liability Component of the Notes (Details)",
     "role": "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
     "shortName": "Debt - Schedule of Net Carrying Amount of the Liability Component of the Notes (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ConvertibleDebtTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i19c8e7d82cba4ba19c4c1649864ca6db_I20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:DebtInstrumentCarryingAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R63": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ConvertibleDebtTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i19c8e7d82cba4ba19c4c1649864ca6db_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "fivn:DebtInstrumentConversionOptionEquityComponent",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2439426 - Disclosure - Debt - Schedule of Net Carrying Amount of Equity Component of the Notes (Details)",
     "role": "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
     "shortName": "Debt - Schedule of Net Carrying Amount of Equity Component of the Notes (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ConvertibleDebtTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i19c8e7d82cba4ba19c4c1649864ca6db_I20191231",
      "decimals": "-3",
      "lang": null,
      "name": "fivn:DebtInstrumentIssuanceCostsEquityComponent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R64": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i9adb54f3624444f4b5c1bbfc2ae3fb8c_D20191001-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:InterestExpense",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2440427 - Disclosure - Debt - Schedule of Interest Expense (Details)",
     "role": "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
     "shortName": "Debt - Schedule of Interest Expense (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "ix:continuation",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i0540306936044eed9f147858aa4ec538_D20190101-20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:InterestExpenseDebt",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R65": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i9a761ead6fd947e0b7d1ac02d1555450_D20180101-20181231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AdjustmentsToAdditionalPaidInCapitalConvertibleDebtWithConversionFeature",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2441428 - Disclosure - Debt - Schedule of Equity Component of Debt (Details)",
     "role": "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
     "shortName": "Debt - Schedule of Equity Component of Debt (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ic1b004b584154510928da8ab1723dbf9_D20180101-20181231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:AdjustmentsToAdditionalPaidInCapitalConvertibleDebtWithConversionFeature",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R66": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i548ab0efd79c4ee2846233dfaced5352_I20160801",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2442429 - Disclosure - Debt - 2016 Loan and Security Agreement (Details)",
     "role": "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails",
     "shortName": "Debt - 2016 Loan and Security Agreement (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i548ab0efd79c4ee2846233dfaced5352_I20160801",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R67": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2443430 - Disclosure - Debt - Schedule of Maturities of Debt (Details)",
     "role": "http://www.five9.com/role/DebtScheduleofMaturitiesofDebtDetails",
     "shortName": "Debt - Schedule of Maturities of Debt (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R68": {
     "firstAnchor": {
      "ancestors": [
       "us-gaap:CommonStockSharesAuthorized",
       "span",
       "div",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:CommonStockSharesAuthorized",
      "reportCount": 1,
      "unitRef": "shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2446431 - Disclosure - Stockholders' Equity - Capital Structure (Details)",
     "role": "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails",
     "shortName": "Stockholders' Equity - Capital Structure (Details)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R69": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "fivn:SummaryofCommonStockReservedforFutureIssuanceTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CommonStockCapitalSharesReservedForFutureIssuance",
      "reportCount": 1,
      "unitRef": "shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2447432 - Disclosure - Stockholders' Equity - Common Stock Reserved for Future Issuance (Details)",
     "role": "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
     "shortName": "Stockholders' Equity - Common Stock Reserved for Future Issuance (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "fivn:SummaryofCommonStockReservedforFutureIssuanceTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i72f1bfe338ed4110ad53462d998b67cc_I20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:CommonStockCapitalSharesReservedForFutureIssuance",
      "reportCount": 1,
      "unique": true,
      "unitRef": "shares",
      "xsiNil": "false"
     }
    },
    "R7": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i0d20343dd83e4149b34b0d37aec4ddcd_D20180101-20181231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PaymentsOfDebtIssuanceCosts",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "statement",
     "isDefault": "false",
     "longName": "1006007 - Statement - Consolidated Statements of Cash Flows (Parenthetical)",
     "role": "http://www.five9.com/role/ConsolidatedStatementsofCashFlowsParenthetical",
     "shortName": "Consolidated Statements of Cash Flows (Parenthetical)",
     "subGroupType": "parenthetical",
     "uniqueAnchor": null
    },
    "R70": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "iaeae60ff8a3e44178c44832bf06dc8c2_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2448433 - Disclosure - Stockholders' Equity - Equity Incentive Plans (Details)",
     "role": "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails",
     "shortName": "Stockholders' Equity - Equity Incentive Plans (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "iaeae60ff8a3e44178c44832bf06dc8c2_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R71": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "us-gaap:ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "2",
      "first": true,
      "lang": null,
      "name": "us-gaap:SharePrice",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usdPerShare",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2449434 - Disclosure - Stockholders' Equity - Stock Option Activities (Details)",
     "role": "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails",
     "shortName": "Stockholders' Equity - Stock Option Activities (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "us-gaap:ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "2",
      "first": true,
      "lang": null,
      "name": "us-gaap:SharePrice",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usdPerShare",
      "xsiNil": "false"
     }
    },
    "R72": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i51d0b1e36d7c4fc7905cc05edd17f682_I20181231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber",
      "reportCount": 1,
      "unitRef": "shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2450435 - Disclosure - Stockholders' Equity - RSU Activities (Details)",
     "role": "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails",
     "shortName": "Stockholders' Equity - RSU Activities (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i255a3000e2f440c49ef8efacb07564b4_D20190101-20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod",
      "reportCount": 1,
      "unique": true,
      "unitRef": "shares",
      "xsiNil": "false"
     }
    },
    "R73": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "fivn:SummaryofCommonStockReservedforFutureIssuanceTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CommonStockCapitalSharesReservedForFutureIssuance",
      "reportCount": 1,
      "unitRef": "shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2451436 - Disclosure - Stockholders' Equity - ESPP (Details)",
     "role": "http://www.five9.com/role/StockholdersEquityESPPDetails",
     "shortName": "Stockholders' Equity - ESPP (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "iea7e09613e5a414c8f8da5259093fc86_I20191231",
      "decimals": "2",
      "lang": null,
      "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate",
      "reportCount": 1,
      "unique": true,
      "unitRef": "number",
      "xsiNil": "false"
     }
    },
    "R74": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AllocatedShareBasedCompensationExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2452437 - Disclosure - Stockholders' Equity - Stock-Based Compensation (Details)",
     "role": "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails",
     "shortName": "Stockholders' Equity - Stock-Based Compensation (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AllocatedShareBasedCompensationExpense",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R75": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i23a61d4afe3a4d8db4f180461966519c_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2453438 - Disclosure - Stockholders' Equity - Option and ESPP Valuation Assumptions (Details)",
     "role": "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails",
     "shortName": "Stockholders' Equity - Option and ESPP Valuation Assumptions (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i23a61d4afe3a4d8db4f180461966519c_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R76": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i9adb54f3624444f4b5c1bbfc2ae3fb8c_D20191001-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:NetIncomeLoss",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2456439 - Disclosure - Net Loss Per Share - Basic and Diluted Net Loss Per Share (Details)",
     "role": "http://www.five9.com/role/NetLossPerShareBasicandDilutedNetLossPerShareDetails",
     "shortName": "Net Loss Per Share - Basic and Diluted Net Loss Per Share (Details)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R77": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "shares",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2457440 - Disclosure - Net Loss Per Share - Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Details)",
     "role": "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails",
     "shortName": "Net Loss Per Share - Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount",
      "reportCount": 1,
      "unique": true,
      "unitRef": "shares",
      "xsiNil": "false"
     }
    },
    "R78": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i19c8e7d82cba4ba19c4c1649864ca6db_I20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:DebtInstrumentConvertibleConversionPrice1",
      "reportCount": 1,
      "unitRef": "usdPerShare",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2458441 - Disclosure - Net Loss Per Share - Narrative (Details)",
     "role": "http://www.five9.com/role/NetLossPerShareNarrativeDetails",
     "shortName": "Net Loss Per Share - Narrative (Details)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R79": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2461442 - Disclosure - Income Taxes - Schedule of Components of Loss before Income Taxes (Details)",
     "role": "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofLossbeforeIncomeTaxesDetails",
     "shortName": "Income Taxes - Schedule of Components of Loss before Income Taxes (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R8": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2101101 - Disclosure - Description of Business and Summary of Significant Accounting Policies",
     "role": "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPolicies",
     "shortName": "Description of Business and Summary of Significant Accounting Policies",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R80": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CurrentFederalTaxExpenseBenefit",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2462443 - Disclosure - Income Taxes - Schedule of Components of Provision for Income Taxes (Details)",
     "role": "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails",
     "shortName": "Income Taxes - Schedule of Components of Provision for Income Taxes (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:CurrentFederalTaxExpenseBenefit",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R81": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate",
      "reportCount": 1,
      "unique": true,
      "unitRef": "number",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2463444 - Disclosure - Income Taxes - Narrative (Details)",
     "role": "http://www.five9.com/role/IncomeTaxesNarrativeDetails",
     "shortName": "Income Taxes - Narrative (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "INF",
      "first": true,
      "lang": null,
      "name": "us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate",
      "reportCount": 1,
      "unique": true,
      "unitRef": "number",
      "xsiNil": "false"
     }
    },
    "R82": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2464445 - Disclosure - Income Taxes - Schedule of Effective Income Tax Amount Reconciliation (Details)",
     "role": "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails",
     "shortName": "Income Taxes - Schedule of Effective Income Tax Amount Reconciliation (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R83": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "fivn:DeferredTaxAssetsOperatingLossandTaxCreditCarryforwardsTotal",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2465446 - Disclosure - Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details)",
     "role": "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails",
     "shortName": "Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "fivn:DeferredTaxAssetsOperatingLossandTaxCreditCarryforwardsTotal",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R84": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "idb9a47ebf5374b02b40416f6cae24e06_I20181231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:UnrecognizedTaxBenefits",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2466447 - Disclosure - Income Taxes - Schedule of Unrecognized Tax Benefits Rollforward (Details)",
     "role": "http://www.five9.com/role/IncomeTaxesScheduleofUnrecognizedTaxBenefitsRollforwardDetails",
     "shortName": "Income Taxes - Schedule of Unrecognized Tax Benefits Rollforward (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ic2715e04acb24e33b5e1b1f0b3ffd8f6_I20161231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:UnrecognizedTaxBenefits",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R85": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:DebtInstrumentCarryingAmount",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2469448 - Disclosure - Commitments and Contingencies - Commitments and Leases (Details)",
     "role": "http://www.five9.com/role/CommitmentsandContingenciesCommitmentsandLeasesDetails",
     "shortName": "Commitments and Contingencies - Commitments and Leases (Details)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R86": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "srt:ContractualObligationFiscalYearMaturityScheduleTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i6b95ae4c237846d889e863c7214b4e60_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PurchaseObligationDueInNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2470449 - Disclosure - Commitments and Contingencies - Hosting, Telecommunications Usage and Maintenance Services (Details)",
     "role": "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails",
     "shortName": "Commitments and Contingencies - Hosting, Telecommunications Usage and Maintenance Services (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "srt:ContractualObligationFiscalYearMaturityScheduleTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i6b95ae4c237846d889e863c7214b4e60_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:PurchaseObligationDueInNextTwelveMonths",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R87": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "fivn:AccruedFederalFees",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2471450 - Disclosure - Commitments and Contingencies - Universal Services Fund Liability (Details)",
     "role": "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails",
     "shortName": "Commitments and Contingencies - Universal Services Fund Liability (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i3082543001344bc290cacef1f7e70a2e_I20150630",
      "decimals": "-5",
      "lang": null,
      "name": "fivn:AccruedFederalFees",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R88": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:SalesAndExciseTaxPayableCurrent",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2472451 - Disclosure - Commitments and Contingencies - State and Local Taxes and Surcharges (Details)",
     "role": "http://www.five9.com/role/CommitmentsandContingenciesStateandLocalTaxesandSurchargesDetails",
     "shortName": "Commitments and Contingencies - State and Local Taxes and Surcharges (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i118aab43eac54979876b688a12321c48_I20191231",
      "decimals": "-5",
      "lang": null,
      "name": "us-gaap:SalesAndExciseTaxPayableCurrentAndNoncurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R89": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i29661ab2b9364a89a9c32e17a259cd32_D20190601-20190630",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:LossContingencyDamagesPaidValue",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2473452 - Disclosure - Commitments and Contingencies - Legal Matters (Details)",
     "role": "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails",
     "shortName": "Commitments and Contingencies - Legal Matters (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i29661ab2b9364a89a9c32e17a259cd32_D20190601-20190630",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:LossContingencyDamagesPaidValue",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R9": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:RevenueFromContractWithCustomerTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2111102 - Disclosure - Revenue",
     "role": "http://www.five9.com/role/Revenue",
     "shortName": "Revenue",
     "subGroupType": "",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:RevenueFromContractWithCustomerTextBlock",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R90": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i9adb54f3624444f4b5c1bbfc2ae3fb8c_D20191001-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2476453 - Disclosure - Geographical Information - Schedule of Revenue and Property and Equipment by Geographic Region (Details)",
     "role": "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails",
     "shortName": "Geographical Information - Schedule of Revenue and Property and Equipment by Geographic Region (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ib3f6d5df8f2c4f51a2c762b1a48ca40a_D20190101-20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R91": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:DefinedContributionPlanCostRecognized",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2478454 - Disclosure - Retirement Plans (Details)",
     "role": "http://www.five9.com/role/RetirementPlansDetails",
     "shortName": "Retirement Plans (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:DefinedContributionPlanCostRecognized",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R92": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "fivn:ScheduleOfBalanceSheetInformationRelatedtoLeasesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseRightOfUseAsset",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2481455 - Disclosure - ASC 842 Adoption Impact - Narrative (Details)",
     "role": "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
     "shortName": "ASC 842 Adoption Impact - Narrative (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "div",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "INF",
      "lang": null,
      "name": "fivn:LesseeOperatingLeaseNumberofLeasesNotYetCommenced",
      "reportCount": 1,
      "unique": true,
      "unitRef": "lease",
      "xsiNil": "false"
     }
    },
    "R93": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseCost",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2482456 - Disclosure - ASC 842 Adoption Impact - Lease Cost and Supplemental Cash Flow (Details)",
     "role": "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails",
     "shortName": "ASC 842 Adoption Impact - Lease Cost and Supplemental Cash Flow (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ifa4c279a958f4a65b702c6050fab8612_D20190101-20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseCost",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R94": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "fivn:ScheduleOfBalanceSheetInformationRelatedtoLeasesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseRightOfUseAsset",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2483457 - Disclosure - ASC 842 Adoption Impact - Balance Sheet Disclosures (Details)",
     "role": "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
     "shortName": "ASC 842 Adoption Impact - Balance Sheet Disclosures (Details)",
     "subGroupType": "details",
     "uniqueAnchor": null
    },
    "R95": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:OperatingLeaseWeightedAverageRemainingLeaseTerm1",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2484458 - Disclosure - ASC 842 Adoption Impact - Weighted Average Remaining Terms and Discount Rates (Details)",
     "role": "http://www.five9.com/role/ASC842AdoptionImpactWeightedAverageRemainingTermsandDiscountRatesDetails",
     "shortName": "ASC 842 Adoption Impact - Weighted Average Remaining Terms and Discount Rates (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "ix:continuation",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": null,
      "first": true,
      "lang": "en-US",
      "name": "us-gaap:OperatingLeaseWeightedAverageRemainingLeaseTerm1",
      "reportCount": 1,
      "unique": true,
      "unitRef": null,
      "xsiNil": "false"
     }
    },
    "R96": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:FinanceLeaseLiabilityMaturityTableTextBlock",
       "us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2485459 - Disclosure - ASC 842 Adoption Impact - Lease Maturities (Details)",
     "role": "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails",
     "shortName": "ASC 842 Adoption Impact - Lease Maturities (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:FinanceLeaseLiabilityMaturityTableTextBlock",
       "us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R97": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "fivn:ScheduleOfBalanceSheetInformationRelatedtoLeasesTableTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i46f4219254f84d079d9baff7b407488a_I20191231",
      "decimals": "-3",
      "first": true,
      "lang": null,
      "name": "us-gaap:OperatingLeaseRightOfUseAsset",
      "reportCount": 1,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2486460 - Disclosure - ASC 842 Adoption Impact - Balance Sheet Impacts (Details)",
     "role": "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
     "shortName": "ASC 842 Adoption Impact - Balance Sheet Impacts (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "td",
       "tr",
       "table",
       "div",
       "us-gaap:ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock",
       "ix:continuation",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "ie361ab64e63e41d392f12fcacb502a94_I20191231",
      "decimals": "-3",
      "lang": null,
      "name": "us-gaap:OperatingLeaseLiabilityCurrent",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R98": {
     "firstAnchor": {
      "ancestors": [
       "ix:continuation",
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i4a14d2cab0094a7a813150d79ed745b7_D20191101-20191130",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "fivn:PaymentsForAssetAcquisition",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2488461 - Disclosure - Acquisition of Whendu LLC (Details)",
     "role": "http://www.five9.com/role/AcquisitionofWhenduLLCDetails",
     "shortName": "Acquisition of Whendu LLC (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "ix:continuation",
       "span",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i4a14d2cab0094a7a813150d79ed745b7_D20191101-20191130",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "fivn:PaymentsForAssetAcquisition",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    },
    "R99": {
     "firstAnchor": {
      "ancestors": [
       "span",
       "ix:continuation",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i348856166dde4567bd03b194b5c91592_D20200115-20200115",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:BusinessCombinationConsiderationTransferred1",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     },
     "groupType": "disclosure",
     "isDefault": "false",
     "longName": "2490462 - Disclosure - Subsequent Events (Details)",
     "role": "http://www.five9.com/role/SubsequentEventsDetails",
     "shortName": "Subsequent Events (Details)",
     "subGroupType": "details",
     "uniqueAnchor": {
      "ancestors": [
       "span",
       "ix:continuation",
       "div",
       "body",
       "html"
      ],
      "baseRef": "fivn-20191231.htm",
      "contextRef": "i348856166dde4567bd03b194b5c91592_D20200115-20200115",
      "decimals": "-5",
      "first": true,
      "lang": null,
      "name": "us-gaap:BusinessCombinationConsiderationTransferred1",
      "reportCount": 1,
      "unique": true,
      "unitRef": "usd",
      "xsiNil": "false"
     }
    }
   },
   "segmentCount": 87,
   "tag": {
    "country_US": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "UNITED STATES",
        "terseLabel": "United States"
       }
      }
     },
     "localname": "US",
     "nsuri": "http://xbrl.sec.gov/country/2017-01-31",
     "presentation": [
      "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "booleanItemType"
    },
    "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_CoverAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Cover page.",
        "label": "Cover page.",
        "terseLabel": "Cover page."
       }
      }
     },
     "localname": "CoverAbstract",
     "nsuri": "http://xbrl.sec.gov/dei/2019-01-31",
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "gMonthDayItemType"
    },
    "dei_DocumentAnnualReport": {
     "auth_ref": [
      "r471"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "fiscalPeriodItemType"
    },
    "dei_DocumentFiscalYearFocus": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "This is focus fiscal year of the document report in CCYY 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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "gYearItemType"
    },
    "dei_DocumentPeriodEndDate": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented.  If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.",
        "label": "Document Period End Date",
        "terseLabel": "Document Period End Date"
       }
      }
     },
     "localname": "DocumentPeriodEndDate",
     "nsuri": "http://xbrl.sec.gov/dei/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "dateItemType"
    },
    "dei_DocumentTransitionReport": {
     "auth_ref": [
      "r470"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "submissionTypeItemType"
    },
    "dei_DocumentsIncorporatedByReferenceTextBlock": {
     "auth_ref": [
      "r468"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_EntityAddressAddressLine2": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Address Line 2 such as Street or Suite number",
        "label": "Entity Address, Address Line Two",
        "terseLabel": "Entity Address, Address Line Two"
       }
      }
     },
     "localname": "EntityAddressAddressLine2",
     "nsuri": "http://xbrl.sec.gov/dei/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_EntityAddressAddressLine3": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Address Line 3 such as an Office Park",
        "label": "Entity Address, Address Line Three",
        "terseLabel": "Entity Address, Address Line Three"
       }
      }
     },
     "localname": "EntityAddressAddressLine3",
     "nsuri": "http://xbrl.sec.gov/dei/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "stateOrProvinceItemType"
    },
    "dei_EntityCentralIndexKey": {
     "auth_ref": [
      "r472"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "yesNoItemType"
    },
    "dei_EntityEmergingGrowthCompany": {
     "auth_ref": [
      "r472"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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": "Entity File Number",
        "terseLabel": "Entity File Number"
       }
      }
     },
     "localname": "EntityFileNumber",
     "nsuri": "http://xbrl.sec.gov/dei/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "fileNumberItemType"
    },
    "dei_EntityFilerCategory": {
     "auth_ref": [
      "r472"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "edgarStateCountryItemType"
    },
    "dei_EntityInteractiveDataCurrent": {
     "auth_ref": [
      "r474"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "monetaryItemType"
    },
    "dei_EntityRegistrantName": {
     "auth_ref": [
      "r472"
     ],
     "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",
        "terseLabel": "Entity Registrant Name"
       }
      }
     },
     "localname": "EntityRegistrantName",
     "nsuri": "http://xbrl.sec.gov/dei/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_EntityShellCompany": {
     "auth_ref": [
      "r472"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_EntitySmallBusiness": {
     "auth_ref": [
      "r472"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "booleanItemType"
    },
    "dei_EntityTaxIdentificationNumber": {
     "auth_ref": [
      "r472"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "yesNoItemType"
    },
    "dei_EntityWellKnownSeasonedIssuer": {
     "auth_ref": [],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "yesNoItemType"
    },
    "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "normalizedStringItemType"
    },
    "dei_Security12bTitle": {
     "auth_ref": [
      "r467"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "securityTitleItemType"
    },
    "dei_SecurityExchangeName": {
     "auth_ref": [
      "r469"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CoverPage"
     ],
     "xbrltype": "tradingSymbolItemType"
    },
    "fivn_AccrualPeriodAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Accrual period for federal fees",
        "label": "Accrual Period [Axis]",
        "terseLabel": "Accrual Period [Axis]"
       }
      }
     },
     "localname": "AccrualPeriodAxis",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "fivn_AccrualPeriodDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "[Domain] for Accrual period for federal fees",
        "label": "Accrual Period [Domain]",
        "terseLabel": "Accrual Period [Domain]"
       }
      }
     },
     "localname": "AccrualPeriodDomain",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_AccruedFederalFees": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_LiabilitiesCurrent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Accrued Federal Fees",
        "label": "Accrued Federal Fees",
        "terseLabel": "Accrued federal fees"
       }
      }
     },
     "localname": "AccruedFederalFees",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_AccruedLiabilitiesandOtherCurrentLiabilities": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_LiabilitiesCurrent",
       "weight": 1.0
      },
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccruedandOtherCurrentLiabilitiesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Accrued Liabilities and Other Current Liabilities",
        "label": "Accrued Liabilities and Other Current Liabilities",
        "terseLabel": "Accrued and other current liabilities",
        "totalLabel": "Accrued and other current liabilities"
       }
      }
     },
     "localname": "AccruedLiabilitiesandOtherCurrentLiabilities",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccruedandOtherCurrentLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_AllowanceForDoubtfulAccountsReceivableWriteOffsNetOfRecoveries": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Allowance For Doubtful Accounts Receivable Write-Offs, Net Of Recoveries",
        "label": "Allowance For Doubtful Accounts Receivable Write-Offs, Net Of Recoveries",
        "negatedTerseLabel": "Less: write-offs, net of recoveries"
       }
      }
     },
     "localname": "AllowanceForDoubtfulAccountsReceivableWriteOffsNetOfRecoveries",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesAllowanceforDoubtfulAccountsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_AmortizationOfOperatingLeaseRightOfUseAssets": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 19.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amortization of Operating Lease Right-of-Use Assets",
        "label": "Amortization of Operating Lease Right-of-Use Assets",
        "terseLabel": "Amortization of operating lease right-of-use assets"
       }
      }
     },
     "localname": "AmortizationOfOperatingLeaseRightOfUseAssets",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_AssetAcquisitionDisclosureTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Asset Acquisition Disclosure",
        "label": "Asset Acquisition Disclosure [Text Block]",
        "terseLabel": "Acquisition of Whendu LLC"
       }
      }
     },
     "localname": "AssetAcquisitionDisclosureTextBlock",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLC"
     ],
     "xbrltype": "textBlockItemType"
    },
    "fivn_AssetAcquisitionsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Asset Acquisitions [Abstract]",
        "label": "Asset Acquisitions [Abstract]"
       }
      }
     },
     "localname": "AssetAcquisitionsAbstract",
     "nsuri": "http://www.five9.com/20191231",
     "xbrltype": "stringItemType"
    },
    "fivn_AssetAcquisitionsLineItemsLineItems": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Asset Acquisitions Line Items",
        "label": "Asset Acquisitions Line Items [Line Items]",
        "terseLabel": "Asset Acquisitions Line Items [Line Items]"
       }
      }
     },
     "localname": "AssetAcquisitionsLineItemsLineItems",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "fivn_AssetAcquisitionsTable": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Asset Acquisitions",
        "label": "Asset Acquisitions [Table]",
        "terseLabel": "Asset Acquisitions [Table]"
       }
      }
     },
     "localname": "AssetAcquisitionsTable",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "fivn_CapitalizationOfLeaseholdImprovementThroughLeaseIncentive": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Capitalization Of Leasehold Improvement Through Lease Incentive",
        "label": "Capitalization Of Leasehold Improvement Through Lease Incentive",
        "terseLabel": "Capitalization of leasehold improvement through non-cash lease incentive"
       }
      }
     },
     "localname": "CapitalizationOfLeaseholdImprovementThroughLeaseIncentive",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_CommonStockAdditionalCapitalSharesReservedforFutureIssuance": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Common Stock, Additional Capital Shares Reserved for Future Issuance",
        "label": "Common Stock, Additional Capital Shares Reserved for Future Issuance",
        "terseLabel": "Shares of common stock reserved for future issuance (in shares)"
       }
      }
     },
     "localname": "CommonStockAdditionalCapitalSharesReservedforFutureIssuance",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "fivn_CommonStockCapitalSharesReservedforFutureIssuanceAnnualIncreasePercentage": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Common Stock, Capital Shares Reserved for Future Issuance, Annual Increase, Percentage",
        "label": "Common Stock, Capital Shares Reserved for Future Issuance, Annual Increase, Percentage",
        "terseLabel": "Automatic annual increase in common stock reserved for issuance, percentage"
       }
      }
     },
     "localname": "CommonStockCapitalSharesReservedforFutureIssuanceAnnualIncreasePercentage",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "fivn_ContingentsalestaxliabilitiesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Contingent sales tax liabilities [Member]",
        "label": "Contingent sales tax liabilities [Member]",
        "terseLabel": "Contingent sales tax liabilities"
       }
      }
     },
     "localname": "ContingentsalestaxliabilitiesMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesStateandLocalTaxesandSurchargesDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_ContractAcquisitionCostsMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Contract Acquisition Costs",
        "label": "Contract Acquisition Costs [Member]",
        "terseLabel": "Contract acquisition costs"
       }
      }
     },
     "localname": "ContractAcquisitionCostsMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/RevenueNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_ContractwithCustomerAssetLiabilityNet": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Contract with Customer, Asset (Liability), Net",
        "label": "Contract with Customer, Asset (Liability), Net",
        "totalLabel": "Net contract assets (liabilities)"
       }
      }
     },
     "localname": "ContractwithCustomerAssetLiabilityNet",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_ConversionFeatureAxisAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Conversion Feature Axis",
        "label": "Conversion Feature Axis [Axis]",
        "terseLabel": "Conversion Feature Axis [Axis]"
       }
      }
     },
     "localname": "ConversionFeatureAxisAxis",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "fivn_ConversionFeatureDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Conversion Feature",
        "label": "Conversion Feature [Domain]",
        "terseLabel": "Conversion Feature [Domain]"
       }
      }
     },
     "localname": "ConversionFeatureDomain",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_ConversionOptionMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Conversion Option",
        "label": "Conversion Option [Member]",
        "terseLabel": "Conversion option"
       }
      }
     },
     "localname": "ConversionOptionMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_ConvertibleSeniorNotesDue2023Member": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Convertible Senior Notes, Due 2023 [Member]",
        "label": "Convertible Senior Notes, Due 2023 [Member]",
        "terseLabel": "Convertible Senior Notes"
       }
      }
     },
     "localname": "ConvertibleSeniorNotesDue2023Member",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_CoordinatedSystemsIncMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Coordinated Systems, Inc",
        "label": "Coordinated Systems, Inc [Member]",
        "terseLabel": "Coordinated Systems, Inc"
       }
      }
     },
     "localname": "CoordinatedSystemsIncMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_DebtInstrumentBasisSpreadonVariableRateIncrease": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Basis Spread on Variable Rate Increase",
        "label": "Debt Instrument, Basis Spread on Variable Rate Increase",
        "terseLabel": "Percentage increase in interest rate if adjusted EBITDA is negative at the end of the quarter"
       }
      }
     },
     "localname": "DebtInstrumentBasisSpreadonVariableRateIncrease",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "fivn_DebtInstrumentCappedCallTransactionsSharesCoverage": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Capped Call Transactions, Shares Coverage",
        "label": "Debt Instrument, Capped Call Transactions, Shares Coverage",
        "terseLabel": "Number of shares covered in the Capped Call Transactions (in shares)"
       }
      }
     },
     "localname": "DebtInstrumentCappedCallTransactionsSharesCoverage",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "fivn_DebtInstrumentConversionOptionEquityComponent": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Conversion Option, Equity Component",
        "label": "Debt Instrument, Conversion Option, Equity Component",
        "verboseLabel": "Conversion option"
       }
      }
     },
     "localname": "DebtInstrumentConversionOptionEquityComponent",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_DebtInstrumentConvertibleAssociatedCappedCallTransactionsAmount": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Convertible, Associated Capped Call Transactions, Amount",
        "label": "Debt Instrument, Convertible, Associated Capped Call Transactions, Amount",
        "verboseLabel": "Cost of Capped Call Transactions recorded in additional paid in capital"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleAssociatedCappedCallTransactionsAmount",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_DebtInstrumentConvertibleCappedCallTransactionsCapPrice": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Convertible, Capped Call Transactions, Cap Price",
        "label": "Debt Instrument, Convertible, Capped Call Transactions, Cap Price",
        "terseLabel": "Cap price of the Capped Call Transactions (in dollars per share)"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleCappedCallTransactionsCapPrice",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "fivn_DebtInstrumentConvertibleConversionPricePerShareRequiringConversion": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Convertible Conversion Price Per Share Requiring Conversion",
        "label": "Debt Instrument, Convertible Conversion Price Per Share Requiring Conversion",
        "terseLabel": "Conversion price per share requiring conversion (in USD per share)"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleConversionPricePerShareRequiringConversion",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "fivn_DebtInstrumentConvertibleTermAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Convertible, Term [Axis]",
        "label": "Debt Instrument, Convertible, Term [Axis]",
        "terseLabel": "Debt Instrument, Convertible, Term [Axis]"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleTermAxis",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "fivn_DebtInstrumentConvertibleTermDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "[Domain] for Debt Instrument, Convertible, Term [Axis]",
        "label": "Debt Instrument, Convertible, Term [Domain]",
        "terseLabel": "Debt Instrument, Convertible, Term [Domain]"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleTermDomain",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_DebtInstrumentConvertibleTermOneMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Convertible, Term One [Member]",
        "label": "Debt Instrument, Convertible, Term One [Member]",
        "terseLabel": "Convertible, term one"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleTermOneMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_DebtInstrumentConvertibleTermTwoMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Convertible, Term Two [Member]",
        "label": "Debt Instrument, Convertible, Term Two [Member]",
        "terseLabel": "Convertible, term two"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleTermTwoMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_DebtInstrumentIssuanceCostsEquityComponent": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debt Instrument, Issuance Costs, Equity Component",
        "label": "Debt Instrument, Issuance Costs, Equity Component",
        "negatedTerseLabel": "Issuance costs"
       }
      }
     },
     "localname": "DebtInstrumentIssuanceCostsEquityComponent",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_DeferredTaxAssetLeaseLiabilities": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 7.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Deferred Tax Asset, Lease Liabilities",
        "label": "Deferred Tax Asset, Lease Liabilities",
        "terseLabel": "Long-term lease liabilities"
       }
      }
     },
     "localname": "DeferredTaxAssetLeaseLiabilities",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_DeferredTaxAssetsOperatingLossandTaxCreditCarryforwardsTotal": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_DeferredTaxAssetsGross",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Deferred Tax Assets, Operating Loss and Tax Credit Carryforwards, Total",
        "label": "Deferred Tax Assets, Operating Loss and Tax Credit Carryforwards, Total",
        "terseLabel": "Net operating loss and credit carryforwards"
       }
      }
     },
     "localname": "DeferredTaxAssetsOperatingLossandTaxCreditCarryforwardsTotal",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_DeferredTaxLiabilitiesDeferredCompensation": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 6.0,
       "parentTag": "us-gaap_DeferredIncomeTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Deferred Tax Liabilities, Deferred Compensation",
        "label": "Deferred Tax Liabilities, Deferred Compensation",
        "negatedLabel": "Deferred compensation - Current"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesDeferredCompensation",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_DeferredTaxLiabilitiesRightOfUseAssets": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 5.0,
       "parentTag": "us-gaap_DeferredIncomeTaxLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Deferred Tax Liabilities, Right-of-use Assets",
        "label": "Deferred Tax Liabilities, Right-of-use Assets",
        "negatedLabel": "Right of use assets"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesRightOfUseAssets",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_DisputedLiabilityRelatedToReversalOfInterestAndPenalties": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disputed Liability Related To Reversal Of Interest And Penalties",
        "label": "Disputed Liability Related To Reversal Of Interest And Penalties",
        "terseLabel": "Disputed liability related to reversal of interest and penalties"
       }
      }
     },
     "localname": "DisputedLiabilityRelatedToReversalOfInterestAndPenalties",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_DisputedportionMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disputed portion [Member]",
        "label": "Disputed portion [Member]",
        "terseLabel": "Disputed portion"
       }
      }
     },
     "localname": "DisputedportionMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_EquipmentMaintenanceServicesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Equipment Maintenance Services [Member]",
        "label": "Equipment Maintenance Services [Member]",
        "terseLabel": "Equipment Maintenance Services"
       }
      }
     },
     "localname": "EquipmentMaintenanceServicesMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_EquityIncentivePlan2004Member": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "2004 Equity Incentive Plan [Member]",
        "label": "Equity Incentive Plan 2004 [Member]",
        "terseLabel": "2004 Equity Incentive Plan"
       }
      }
     },
     "localname": "EquityIncentivePlan2004Member",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_EquityIncentivePlan2014Member": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "2014 Equity Incentive Plan [Member]",
        "label": "Equity Incentive Plan 2014 [Member]",
        "terseLabel": "Shares available for future grant under 2014 Plan",
        "verboseLabel": "2014 Equity Incentive Plan"
       }
      }
     },
     "localname": "EquityIncentivePlan2014Member",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_FinanceLeaseCost": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails": {
       "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.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_FinanceLeaseRightOfUseAssetAccumulatedAmortization": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCapitalLeasedPropertyandEquipmentDetails": {
       "order": 1.0,
       "parentTag": "fivn_FinanceLeaseRightOfUseAssetAfterAccumulatedAmortization",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Finance Lease, Right-of-Use Asset, Accumulated Amortization",
        "label": "Finance Lease, Right-of-Use Asset, Accumulated Amortization",
        "negatedLabel": "Finance Lease, Right-of-Use Asset, Accumulated Amortization",
        "negatedTerseLabel": "Less: accumulated depreciation and amortization"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAssetAccumulatedAmortization",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCapitalLeasedPropertyandEquipmentDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_FinanceLeaseRightOfUseAssetAfterAccumulatedAmortization": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCapitalLeasedPropertyandEquipmentDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Finance Lease, Right-of-Use Asset, after Accumulated Amortization",
        "label": "Finance Lease, Right-of-Use Asset, after Accumulated Amortization",
        "terseLabel": "Total",
        "totalLabel": "Total"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAssetAfterAccumulatedAmortization",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCapitalLeasedPropertyandEquipmentDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCapitalLeasedPropertyandEquipmentDetails": {
       "order": 2.0,
       "parentTag": "fivn_FinanceLeaseRightOfUseAssetAfterAccumulatedAmortization",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Finance Lease, Right-of-Use Asset, before Accumulated Amortization",
        "label": "Finance Lease, Right-of-Use Asset, before Accumulated Amortization",
        "terseLabel": "Gross"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCapitalLeasedPropertyandEquipmentDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_FinancialStatementComponentsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Financial Statement Components [Abstract]",
        "label": "Financial Statement Components [Abstract]",
        "terseLabel": "Financial Statement Components [Abstract]"
       }
      }
     },
     "localname": "FinancialStatementComponentsAbstract",
     "nsuri": "http://www.five9.com/20191231",
     "xbrltype": "stringItemType"
    },
    "fivn_HostingServicesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Hosting Services",
        "label": "Hosting Services [Member]",
        "terseLabel": "Hosting Services"
       }
      }
     },
     "localname": "HostingServicesMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_IncreaseDecreaseOfInterestAndPenaltiesRelatedToAccruedFederalFees": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 6.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Increase (Decrease) Of Interest And Penalties Related To Accrued Federal Fees",
        "label": "Increase (Decrease) Of Interest And Penalties Related To Accrued Federal Fees",
        "terseLabel": "Reversal of interest and penalties on accrued federal fees"
       }
      }
     },
     "localname": "IncreaseDecreaseOfInterestAndPenaltiesRelatedToAccruedFederalFees",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_IncreaseDecreaseinAccruedLiabilitiesandOtherCurrentLiabilities": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 14.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Increase (Decrease) in Accrued Liabilities and Other Current Liabilities",
        "label": "Increase (Decrease) in Accrued Liabilities and Other Current Liabilities",
        "terseLabel": "Accrued and other current liabilities"
       }
      }
     },
     "localname": "IncreaseDecreaseinAccruedLiabilitiesandOtherCurrentLiabilities",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_IncreaseDecreaseinCapitalizedContractCost": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 11.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Increase (Decrease) in Capitalized Contract Cost",
        "label": "Increase (Decrease) in Capitalized Contract Cost",
        "negatedTerseLabel": "Deferred contract acquisition costs"
       }
      }
     },
     "localname": "IncreaseDecreaseinCapitalizedContractCost",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_InvestmentsAndFairValueMeasurementsTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Investments And Fair Value Measurements [Text Block]",
        "label": "Investments And Fair Value Measurements [Text Block]",
        "terseLabel": "Investments and Fair Value Measurements"
       }
      }
     },
     "localname": "InvestmentsAndFairValueMeasurementsTextBlock",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurements"
     ],
     "xbrltype": "textBlockItemType"
    },
    "fivn_IssuanceCostsMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Issuance Costs",
        "label": "Issuance Costs [Member]",
        "terseLabel": "Issuance costs"
       }
      }
     },
     "localname": "IssuanceCostsMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_LesseeOperatingLeaseLeaseNotYetCommencedAmount": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Lessee, Operating Lease, Lease Not Yet Commenced, Amount",
        "label": "Lessee, Operating Lease, Lease Not Yet Commenced, Amount",
        "terseLabel": "Amount of lease obligation, not yet commenced"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLeaseNotYetCommencedAmount",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_LesseeOperatingLeaseNumberofLeasesNotYetCommenced": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Lessee, Operating Lease, Number of Leases Not Yet Commenced",
        "label": "Lessee, Operating Lease, Number of Leases Not Yet Commenced",
        "terseLabel": "Number of operating leases not yet commenced (in leases)"
       }
      }
     },
     "localname": "LesseeOperatingLeaseNumberofLeasesNotYetCommenced",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails"
     ],
     "xbrltype": "integerItemType"
    },
    "fivn_LineofCreditFacilityFirstandSecondAnniversaryFee": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Line of Credit Facility, First and Second Anniversary Fee",
        "label": "Line of Credit Facility, First and Second Anniversary Fee",
        "terseLabel": "First and second anniversary fee for line of credit"
       }
      }
     },
     "localname": "LineofCreditFacilityFirstandSecondAnniversaryFee",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_LoanandSecurityAgreement2016Member": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Loan and Security Agreement 2016 [Member]",
        "label": "Loan and Security Agreement 2016 [Member]",
        "terseLabel": "Loan and Security Agreement 2016"
       }
      }
     },
     "localname": "LoanandSecurityAgreement2016Member",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_MelcherLitigationMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Melcher Litigation [Member]",
        "label": "Melcher Litigation [Member]",
        "terseLabel": "Melcher Litigation"
       }
      }
     },
     "localname": "MelcherLitigationMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_NoncashOrPartNoncashAcquisitionTransactionCostsAccrued": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Noncash or Part Noncash Acquisition, Transaction Costs Accrued",
        "label": "Noncash or Part Noncash Acquisition, Transaction Costs Accrued",
        "terseLabel": "Acquisition and related transaction costs accrued at period-end"
       }
      }
     },
     "localname": "NoncashOrPartNoncashAcquisitionTransactionCostsAccrued",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_OperatingLeaseRightOfUseAssetGross": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Operating Lease, Right-Of-Use Asset Gross",
        "label": "Operating Lease, Right-Of-Use Asset Gross",
        "terseLabel": "Operating lease right-of-use asset gross"
       }
      }
     },
     "localname": "OperatingLeaseRightOfUseAssetGross",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_OperatingLossCarryforwardLimitationsonUseChangeinOwnership": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Operating Loss Carryforward, Limitations on Use, Change in Ownership",
        "label": "Operating Loss Carryforward, Limitations on Use, Change in Ownership",
        "terseLabel": "Limitation on use of net operating loss, cumulative ownership change, more than"
       }
      }
     },
     "localname": "OperatingLossCarryforwardLimitationsonUseChangeinOwnership",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "fivn_OperatingLossCarryforwardLimitationsonUseChangeinOwnershipPeriod": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Operating Loss Carryforward, Limitations on Use, Change in Ownership, Period",
        "label": "Operating Loss Carryforward, Limitations on Use, Change in Ownership, Period",
        "terseLabel": "Limitation on use of net operating loss, cumulative ownership change, period of change"
       }
      }
     },
     "localname": "OperatingLossCarryforwardLimitationsonUseChangeinOwnershipPeriod",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "fivn_PaymentsForAssetAcquisition": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Payments for Asset Acquisition",
        "label": "Payments for Asset Acquisition",
        "terseLabel": "Payments for asset acquisition"
       }
      }
     },
     "localname": "PaymentsForAssetAcquisition",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_PaymentsForCappedCallTransactionMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Payments For Capped Call Transaction",
        "label": "Payments For Capped Call Transaction [Member]",
        "terseLabel": "Payments for capped call transactions"
       }
      }
     },
     "localname": "PaymentsForCappedCallTransactionMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_PaymentsForCappedCallTransactionsFinancingActivities": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 2.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Payments For Capped Call Transactions, Financing Activities",
        "label": "Payments For Capped Call Transactions, Financing Activities",
        "negatedTerseLabel": "Payments for capped call transactions"
       }
      }
     },
     "localname": "PaymentsForCappedCallTransactionsFinancingActivities",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_PaymentstoAcquireConvertibleNotesHeldforInvestment": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 4.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Payments to Acquire Convertible Notes Held for Investment",
        "label": "Payments to Acquire Convertible Notes Held for Investment",
        "negatedTerseLabel": "Cash paid to acquire substantially all of the assets of Whendu, LLC"
       }
      }
     },
     "localname": "PaymentstoAcquireConvertibleNotesHeldforInvestment",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_ProceedsFromStockOptionsAndWarrantsExercised": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 3.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Proceeds From Stock Options And Warrants Exercised",
        "label": "Proceeds From Stock Options And Warrants Exercised",
        "terseLabel": "Proceeds from exercise of common stock options"
       }
      }
     },
     "localname": "ProceedsFromStockOptionsAndWarrantsExercised",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_SalesandExciseTaxesPayableNoncurrent": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_Liabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Sales and excise taxes payable, noncurrent",
        "label": "Sales and Excise Taxes Payable, Noncurrent",
        "terseLabel": "Sales tax liabilities \u2014 less current portion"
       }
      }
     },
     "localname": "SalesandExciseTaxesPayableNoncurrent",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_ScheduleOfBalanceSheetInformationRelatedtoLeasesTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Schedule Of Balance Sheet Information Related to Leases [Table Text Block]",
        "label": "Schedule Of Balance Sheet Information Related to Leases [Table Text Block]",
        "terseLabel": "Schedule of balance sheet information related to leases"
       }
      }
     },
     "localname": "ScheduleOfBalanceSheetInformationRelatedtoLeasesTableTextBlock",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "fivn_SharebasedCompensationArrangementbySharebasedPaymentAwardExpirationPeriodofVestedAward": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period of Vested Award",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period of Vested Award",
        "terseLabel": "Expiration period, after termination of employment or relationship of consultant or director"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementbySharebasedPaymentAwardExpirationPeriodofVestedAward",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "fivn_SharebasedCompensationArrangementbySharebasedPaymentAwardMaximumAnnualIncreaseofSharesAuthorized": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Share-based Compensation Arrangement by Share-based Payment Award, Maximum Annual Increase of Shares Authorized",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Maximum Annual Increase of Shares Authorized",
        "terseLabel": "Maximum annual increase of shares reserved (in shares)"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementbySharebasedPaymentAwardMaximumAnnualIncreaseofSharesAuthorized",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "fivn_StockIssuedDuringPeriodSharesStockOptionsandWarrantsExercised": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Stock Issued During Period, Shares, Stock Options and Warrants Exercised",
        "label": "Stock Issued During Period, Shares, Stock Options and Warrants Exercised",
        "terseLabel": "Issuance of common stock upon exercise of stock options and warrants (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesStockOptionsandWarrantsExercised",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "sharesItemType"
    },
    "fivn_StockIssuedDuringPeriodValueStockOptionsandWarrantsExercised": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Stock Issued During Period, Value, Stock Options and Warrants Exercised",
        "label": "Stock Issued During Period, Value, Stock Options and Warrants Exercised",
        "terseLabel": "Issuance of common stock upon exercise of stock options and warrants"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValueStockOptionsandWarrantsExercised",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "monetaryItemType"
    },
    "fivn_SummaryofCommonStockReservedforFutureIssuanceTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Summary of Common Stock Reserved for Future Issuance [Table Text Block]",
        "label": "Summary of Common Stock Reserved for Future Issuance [Table Text Block]",
        "terseLabel": "Schedule of common stock reserved for future issuance"
       }
      }
     },
     "localname": "SummaryofCommonStockReservedforFutureIssuanceTableTextBlock",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "fivn_TelecommunicationUsageServicesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Telecommunication Usage Services",
        "label": "Telecommunication Usage Services [Member]",
        "terseLabel": "Telecommunication Usage Services"
       }
      }
     },
     "localname": "TelecommunicationUsageServicesMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_U.S.AgencySecuritiesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "U.S. Agency Securities [Member]",
        "label": "U.S. Agency Securities [Member]",
        "terseLabel": "U.S. agency securities"
       }
      }
     },
     "localname": "U.S.AgencySecuritiesMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_U.S.TreasuryMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "U.S. Treasury [Member]",
        "label": "U.S. Treasury [Member]",
        "terseLabel": "U.S. Treasury"
       }
      }
     },
     "localname": "U.S.TreasuryMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_USFobligationsMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "USF obligations [Member]",
        "label": "USF obligations [Member]",
        "terseLabel": "USF Obligations"
       }
      }
     },
     "localname": "USFobligationsMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_UniversalServicesFundCivilPenaltyMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Universal Services Fund, Civil Penalty",
        "label": "Universal Services Fund, Civil Penalty [Member]",
        "terseLabel": "Civil penalty"
       }
      }
     },
     "localname": "UniversalServicesFundCivilPenaltyMember",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_Year2003ToYear2007Member": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Year 2003 To Year 2007 [Member]",
        "label": "Year 2003 To Year 2007 [Member]",
        "terseLabel": "Year 2003 To Year 2007"
       }
      }
     },
     "localname": "Year2003ToYear2007Member",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "fivn_Year2008Through2012Member": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Year 2008 through 2012",
        "label": "Year 2008 through 2012 [Member]",
        "terseLabel": "Year 2008 through 2012"
       }
      }
     },
     "localname": "Year2008Through2012Member",
     "nsuri": "http://www.five9.com/20191231",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_BoardOfDirectorsChairmanMember": {
     "auth_ref": [
      "r156"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Leader of board of directors.",
        "label": "Board of Directors Chairman [Member]",
        "terseLabel": "Board of Directors Executive Chairman"
       }
      }
     },
     "localname": "BoardOfDirectorsChairmanMember",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_ContractualObligationFiscalYearMaturityScheduleTableTextBlock": {
     "auth_ref": [
      "r473"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of contractual obligation by timing of payment due. Includes, but is not limited to, long-term debt obligation, lease obligation, and purchase obligation.",
        "label": "Contractual Obligation, Fiscal Year Maturity [Table Text Block]",
        "terseLabel": "Schedule of future minimum lease payments for hosting, telecommunication usage, and maintenance services"
       }
      }
     },
     "localname": "ContractualObligationFiscalYearMaturityScheduleTableTextBlock",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "srt_LitigationCaseAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of judicial proceeding, alternative dispute resolution or claim.",
        "label": "Litigation Case [Axis]",
        "terseLabel": "Litigation Case [Axis]"
       }
      }
     },
     "localname": "LitigationCaseAxis",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_LitigationCaseTypeDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Judicial proceeding, alternative dispute resolution or claim. For example, but not limited to, name of case, category of litigation, or other differentiating information.",
        "label": "Litigation Case [Domain]",
        "terseLabel": "Litigation Case [Domain]"
       }
      }
     },
     "localname": "LitigationCaseTypeDomain",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_MaximumMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Upper limit of the provided range.",
        "label": "Maximum [Member]",
        "terseLabel": "Maximum"
       }
      }
     },
     "localname": "MaximumMember",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesGoodwillandIntangibleAssetsDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails",
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_MinimumMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Lower limit of the provided range.",
        "label": "Minimum [Member]",
        "terseLabel": "Minimum"
       }
      }
     },
     "localname": "MinimumMember",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesGoodwillandIntangibleAssetsDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails",
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_RangeAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by statistical measurement. Includes, but is not limited to, minimum, maximum, weighted average, arithmetic average, and median.",
        "label": "Statistical Measurement [Axis]",
        "terseLabel": "Range [Axis]"
       }
      }
     },
     "localname": "RangeAxis",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesGoodwillandIntangibleAssetsDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails",
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_RangeMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Statistical measurement. Includes, but is not limited to, minimum, maximum, weighted average, arithmetic average, and median.",
        "label": "Statistical Measurement [Domain]",
        "terseLabel": "Range [Domain]"
       }
      }
     },
     "localname": "RangeMember",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesGoodwillandIntangibleAssetsDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails",
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_RestatementAdjustmentMember": {
     "auth_ref": [
      "r116",
      "r119",
      "r120",
      "r121"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Effect of a correction of an error, other prior year adjustment, or application of a new accounting pronouncement on a financial statement line item or any per share amounts. The cumulative effect of the change on retained earnings or net assets in the statement of financial position would also be represented under this domain member.",
        "label": "Restatement Adjustment [Member]",
        "terseLabel": "Adjustment"
       }
      }
     },
     "localname": "RestatementAdjustmentMember",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_RestatementAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by revision of previously issued financial statements.",
        "label": "Restatement [Axis]",
        "terseLabel": "Restatement [Axis]"
       }
      }
     },
     "localname": "RestatementAxis",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_RestatementDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Revision of previously issued financial statements.",
        "label": "Restatement [Domain]",
        "terseLabel": "Restatement [Domain]"
       }
      }
     },
     "localname": "RestatementDomain",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_ScenarioPreviouslyReportedMember": {
     "auth_ref": [
      "r119",
      "r120",
      "r121"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Represents the amount as previously reported before the correction of an error or other adjustment.",
        "label": "Previously Reported [Member]",
        "terseLabel": "Previously reported"
       }
      }
     },
     "localname": "ScenarioPreviouslyReportedMember",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_SegmentGeographicalDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Geographical area.",
        "label": "Geographical [Domain]",
        "terseLabel": "Geographical [Domain]"
       }
      }
     },
     "localname": "SegmentGeographicalDomain",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "srt_StatementGeographicalAxis": {
     "auth_ref": [
      "r154",
      "r265",
      "r268",
      "r462",
      "r463",
      "r465",
      "r475",
      "r476"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by geographical components.",
        "label": "Geographical [Axis]",
        "terseLabel": "Geographical [Axis]"
       }
      }
     },
     "localname": "StatementGeographicalAxis",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_TitleOfIndividualAxis": {
     "auth_ref": [
      "r156",
      "r420"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by title of individual or nature of relationship to individual or group of individuals.",
        "label": "Title of Individual [Axis]",
        "terseLabel": "Title of Individual [Axis]"
       }
      }
     },
     "localname": "TitleOfIndividualAxis",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "srt_TitleOfIndividualWithRelationshipToEntityDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Title of individual, or nature of relationship to individual or group of individuals.",
        "label": "Title of Individual [Domain]",
        "terseLabel": "Relationship to Entity [Domain]"
       }
      }
     },
     "localname": "TitleOfIndividualWithRelationshipToEntityDomain",
     "nsuri": "http://fasb.org/srt/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AccountingPoliciesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Accounting Policies [Abstract]",
        "terseLabel": "Accounting Policies [Abstract]"
       }
      }
     },
     "localname": "AccountingPoliciesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccountingStandardsUpdate201409Member": {
     "auth_ref": [
      "r269"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Accounting Standards Update 2014-09 Revenue from Contracts with Customers (Topic 606).",
        "label": "Accounting Standards Update 2014-09 [Member]",
        "terseLabel": "ASU 2014-09",
        "verboseLabel": "ASC 606"
       }
      }
     },
     "localname": "AccountingStandardsUpdate201409Member",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AccountingStandardsUpdate201602Member": {
     "auth_ref": [
      "r401"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Accounting Standards Update 2016-02 Leases (Topic 842).",
        "label": "Accounting Standards Update 2016-02 [Member]",
        "terseLabel": "ASU 2016-02"
       }
      }
     },
     "localname": "AccountingStandardsUpdate201602Member",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AccountingStandardsUpdate201609Member": {
     "auth_ref": [
      "r315",
      "r316",
      "r317",
      "r318",
      "r319",
      "r320",
      "r321",
      "r322",
      "r323",
      "r324"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Accounting Standards Update 2016-09 Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting.",
        "label": "Accounting Standards Update 2016-09 [Member]",
        "terseLabel": "ASU 2016-09"
       }
      }
     },
     "localname": "AccountingStandardsUpdate201609Member",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "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 Receivable"
       }
      }
     },
     "localname": "AccountsNotesAndLoansReceivableLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccountsNotesLoansAndFinancingReceivablesByBillingStatusTypeAxis": {
     "auth_ref": [
      "r46"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by billing status of receivables.",
        "label": "Billing Status, Type [Axis]",
        "terseLabel": "Billing Status, Type [Axis]"
       }
      }
     },
     "localname": "AccountsNotesLoansAndFinancingReceivablesByBillingStatusTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AccountsPayableCurrent": {
     "auth_ref": [
      "r33"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "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"
       }
      }
     },
     "localname": "AccountsPayableCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccountsReceivableGrossCurrent": {
     "auth_ref": [
      "r157",
      "r158"
     ],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_AccountsReceivableNetCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount, before 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, before Allowance for Credit Loss, Current",
        "terseLabel": "Trade accounts receivable"
       }
      }
     },
     "localname": "AccountsReceivableGrossCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccountsReceivableNetCurrent": {
     "auth_ref": [
      "r2",
      "r19",
      "r157",
      "r158",
      "r266"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_AssetsCurrent",
       "weight": 1.0
      },
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments": {
     "auth_ref": [
      "r94"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 2.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.",
        "label": "Accretion (Amortization) of Discounts and Premiums, Investments",
        "negatedTerseLabel": "Amortization of premium on marketable investments"
       }
      }
     },
     "localname": "AccretionAmortizationOfDiscountsAndPremiumsInvestments",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccruedLiabilitiesCurrent": {
     "auth_ref": [
      "r36"
     ],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccruedandOtherCurrentLiabilitiesDetails": {
       "order": 1.0,
       "parentTag": "fivn_AccruedLiabilitiesandOtherCurrentLiabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).",
        "label": "Accrued Liabilities, Current",
        "verboseLabel": "Accrued expenses"
       }
      }
     },
     "localname": "AccruedLiabilitiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccruedandOtherCurrentLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment": {
     "auth_ref": [
      "r31",
      "r213"
     ],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails": {
       "order": 2.0,
       "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",
        "negatedTerseLabel": "Accumulated depreciation and amortization"
       }
      }
     },
     "localname": "AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax": {
     "auth_ref": [
      "r51",
      "r52",
      "r53"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "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 income (loss)"
       }
      }
     },
     "localname": "AccumulatedOtherComprehensiveIncomeLossNetOfTax",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AccumulatedOtherComprehensiveIncomeMember": {
     "auth_ref": [
      "r50",
      "r53",
      "r54",
      "r380"
     ],
     "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 Income (Loss)"
       }
      }
     },
     "localname": "AccumulatedOtherComprehensiveIncomeMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems": {
     "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": "Acquired Finite-Lived Intangible Assets [Line Items]",
        "terseLabel": "Acquired Finite-Lived Intangible Assets"
       }
      }
     },
     "localname": "AcquiredFiniteLivedIntangibleAssetsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AdditionalPaidInCapital": {
     "auth_ref": [
      "r20"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 3.0,
       "parentTag": "us-gaap_StockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "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. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.",
        "label": "Additional Paid in Capital",
        "terseLabel": "Additional paid-in capital"
       }
      }
     },
     "localname": "AdditionalPaidInCapital",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AdditionalPaidInCapitalMember": {
     "auth_ref": [],
     "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"
       }
      }
     },
     "localname": "AdditionalPaidInCapitalMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_AdjustmentsForNewAccountingPronouncementsAxis": {
     "auth_ref": [
      "r115"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by new accounting pronouncement.",
        "label": "Adjustments for New Accounting Pronouncements [Axis]",
        "terseLabel": "Adjustments for New Accounting Pronouncements [Axis]"
       }
      }
     },
     "localname": "AdjustmentsForNewAccountingPronouncementsAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement.",
        "label": "Share-based Payment Arrangement, Decrease for Tax Withholding Obligation",
        "negatedTerseLabel": "Shares held for tax withholdings"
       }
      }
     },
     "localname": "AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AdjustmentsToAdditionalPaidInCapitalConvertibleDebtWithConversionFeature": {
     "auth_ref": [
      "r249",
      "r257",
      "r361"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of increase (decrease) in additional paid in capital (APIC) resulting from recognition of deferred taxes for convertible debt with a beneficial conversion feature.",
        "label": "Adjustments to Additional Paid in Capital, Convertible Debt with Conversion Feature",
        "terseLabel": "Equity component of issuance of convertible senior notes"
       }
      }
     },
     "localname": "AdjustmentsToAdditionalPaidInCapitalConvertibleDebtWithConversionFeature",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AdjustmentsToAdditionalPaidInCapitalOther": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of other increase (decrease) in additional paid in capital (APIC).",
        "label": "Adjustments to Additional Paid in Capital, Other",
        "terseLabel": "Other"
       }
      }
     },
     "localname": "AdjustmentsToAdditionalPaidInCapitalOther",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue": {
     "auth_ref": [
      "r277",
      "r279",
      "r327",
      "r328"
     ],
     "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"
       }
      }
     },
     "localname": "AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AdvertisingCostsPolicyTextBlock": {
     "auth_ref": [
      "r330"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_AdvertisingExpense": {
     "auth_ref": [
      "r331"
     ],
     "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 expense"
       }
      }
     },
     "localname": "AdvertisingExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesAdvertisingCostsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AllocatedShareBasedCompensationExpense": {
     "auth_ref": [
      "r279",
      "r311",
      "r326"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AllowanceForDoubtfulAccountsReceivable": {
     "auth_ref": [
      "r160",
      "r173",
      "r175",
      "r177"
     ],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_AccountsReceivableNetCurrent",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of allowance for credit loss on accounts receivable.",
        "label": "Accounts Receivable, Allowance for Credit Loss",
        "negatedTerseLabel": "Allowance for doubtful accounts",
        "periodEndLabel": "Balance, end of period",
        "periodStartLabel": "Balance, beginning of period"
       }
      }
     },
     "localname": "AllowanceForDoubtfulAccountsReceivable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesAllowanceforDoubtfulAccountsDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward": {
     "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": "Accounts Receivable, Allowance for Credit Loss [Roll Forward]",
        "terseLabel": "Allowance for Doubtful Accounts Receivable [Roll Forward]"
       }
      }
     },
     "localname": "AllowanceForDoubtfulAccountsReceivableRollforward",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesAllowanceforDoubtfulAccountsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AmortizationOfDebtDiscountPremium": {
     "auth_ref": [
      "r76",
      "r93",
      "r396"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_InterestExpense",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.",
        "label": "Amortization of Debt Discount (Premium)",
        "terseLabel": "Amortization of debt discount"
       }
      }
     },
     "localname": "AmortizationOfDebtDiscountPremium",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AmortizationOfFinancingCosts": {
     "auth_ref": [
      "r70",
      "r93",
      "r398"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails": {
       "order": 3.0,
       "parentTag": "us-gaap_InterestExpense",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of amortization expense attributable to debt issuance costs.",
        "label": "Amortization of Debt Issuance Costs",
        "terseLabel": "Amortization of issuance costs"
       }
      }
     },
     "localname": "AmortizationOfFinancingCosts",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AmortizationOfFinancingCostsAndDiscounts": {
     "auth_ref": [
      "r93",
      "r398"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 5.0,
       "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"
       }
      }
     },
     "localname": "AmortizationOfFinancingCostsAndDiscounts",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AmortizationOfIntangibleAssets": {
     "auth_ref": [
      "r93",
      "r198",
      "r206"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount": {
     "auth_ref": [
      "r128"
     ],
     "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": "Anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)"
       }
      }
     },
     "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis": {
     "auth_ref": [
      "r128"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of antidilutive security.",
        "label": "Antidilutive Securities [Axis]",
        "terseLabel": "Antidilutive Securities [Axis]"
       }
      }
     },
     "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails",
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "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"
       }
      }
     },
     "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AntidilutiveSecuritiesNameDomain": {
     "auth_ref": [
      "r128"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "AntidilutiveSecuritiesNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails",
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_Assets": {
     "auth_ref": [
      "r153",
      "r432",
      "r452"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AssetsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Assets [Abstract]",
        "terseLabel": "ASSETS",
        "verboseLabel": "Assets"
       }
      }
     },
     "localname": "AssetsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AssetsCurrent": {
     "auth_ref": [
      "r4",
      "r6",
      "r48"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 1.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_AssetsFairValueDisclosure": {
     "auth_ref": [
      "r383"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.",
        "label": "Assets, Fair Value Disclosure",
        "terseLabel": "Assets measured at fair value on nonrecurring basis"
       }
      }
     },
     "localname": "AssetsFairValueDisclosure",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax": {
     "auth_ref": [
      "r168"
     ],
     "calculation": {
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).",
        "label": "Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax",
        "terseLabel": "Gross Unrealized Gains"
       }
      }
     },
     "localname": "AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax": {
     "auth_ref": [
      "r169"
     ],
     "calculation": {
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).",
        "label": "Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax",
        "negatedTerseLabel": "Gross Unrealized Losses"
       }
      }
     },
     "localname": "AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis": {
     "auth_ref": [
      "r166",
      "r182"
     ],
     "calculation": {
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).",
        "label": "Debt Securities, Available-for-sale, Amortized Cost",
        "totalLabel": "Cost"
       }
      }
     },
     "localname": "AvailableForSaleDebtSecuritiesAmortizedCostBasis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AvailableForSaleSecuritiesDebtSecurities": {
     "auth_ref": [
      "r163",
      "r167",
      "r182"
     ],
     "calculation": {
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails": {
       "order": 3.0,
       "parentTag": "us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).",
        "label": "Debt Securities, Available-for-sale",
        "terseLabel": "Fair Value",
        "verboseLabel": "Marketable investments"
       }
      }
     },
     "localname": "AvailableForSaleSecuritiesDebtSecurities",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AvailableForSaleSecuritiesDebtSecuritiesCurrent": {
     "auth_ref": [
      "r165",
      "r182"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_AssetsCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.",
        "label": "Debt Securities, Available-for-sale, Current",
        "terseLabel": "Marketable investments"
       }
      }
     },
     "localname": "AvailableForSaleSecuritiesDebtSecuritiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_AwardTypeAxis": {
     "auth_ref": [
      "r281",
      "r313"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of award under share-based payment arrangement.",
        "label": "Award Type [Axis]",
        "terseLabel": "Award Type [Axis]"
       }
      }
     },
     "localname": "AwardTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails",
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails",
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails",
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_BasisOfAccountingPolicyPolicyTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for basis of accounting, or basis of presentation, used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).",
        "label": "Basis of Accounting, Policy [Policy Text Block]",
        "terseLabel": "Basis of Presentation"
       }
      }
     },
     "localname": "BasisOfAccountingPolicyPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_BilledRevenuesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Billed amounts due for services rendered or products shipped. This element is distinct from Billed contracts receivables because this is based on noncontract transactions.",
        "label": "Billed Revenues [Member]",
        "terseLabel": "Trade accounts receivable"
       }
      }
     },
     "localname": "BilledRevenuesMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_BusinessAcquisitionAcquireeDomain": {
     "auth_ref": [],
     "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 [Domain]"
       }
      }
     },
     "localname": "BusinessAcquisitionAcquireeDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_BusinessAcquisitionAxis": {
     "auth_ref": [
      "r367",
      "r368"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by business combination or series of individually immaterial business combinations.",
        "label": "Business Acquisition [Axis]",
        "terseLabel": "Business Acquisition [Axis]"
       }
      }
     },
     "localname": "BusinessAcquisitionAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_BusinessCombinationConsiderationTransferred1": {
     "auth_ref": [
      "r372",
      "r373",
      "r374"
     ],
     "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": "Cash consideration"
       }
      }
     },
     "localname": "BusinessCombinationConsiderationTransferred1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CapitalExpendituresIncurredButNotYetPaid": {
     "auth_ref": [
      "r98",
      "r99",
      "r100"
     ],
     "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": "Equipment purchased and unpaid at period-end"
       }
      }
     },
     "localname": "CapitalExpendituresIncurredButNotYetPaid",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CapitalizedContractCostAmortizationPeriod": {
     "auth_ref": [
      "r190"
     ],
     "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": "Amortization period of capitalized contract cost"
       }
      }
     },
     "localname": "CapitalizedContractCostAmortizationPeriod",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RevenueNarrativeDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_CapitalizedContractCostAxis": {
     "auth_ref": [
      "r191"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by cost capitalized in obtaining or fulfilling contract with customer.",
        "label": "Capitalized Contract Cost [Axis]",
        "terseLabel": "Capitalized Contract Cost [Axis]"
       }
      }
     },
     "localname": "CapitalizedContractCostAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RevenueNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CapitalizedContractCostDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Cost capitalized in obtaining and fulfilling contract with customer.",
        "label": "Capitalized Contract Cost [Domain]",
        "terseLabel": "Capitalized Contract Cost [Domain]"
       }
      }
     },
     "localname": "CapitalizedContractCostDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RevenueNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CapitalizedContractCostNet": {
     "auth_ref": [
      "r191"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "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.",
        "label": "Capitalized Contract Cost, Net",
        "terseLabel": "Deferred contract acquisition costs",
        "totalLabel": "Total deferred contract acquisition costs"
       }
      }
     },
     "localname": "CapitalizedContractCostNet",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CapitalizedContractCostNetCurrent": {
     "auth_ref": [
      "r191"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_CapitalizedContractCostNet",
       "weight": 1.0
      },
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 5.0,
       "parentTag": "us-gaap_AssetsCurrent",
       "weight": 1.0
      }
     },
     "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": "Deferred contract acquisition costs",
        "verboseLabel": "Deferred contract acquisition costs, current"
       }
      }
     },
     "localname": "CapitalizedContractCostNetCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CapitalizedContractCostNetNoncurrent": {
     "auth_ref": [
      "r191"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_CapitalizedContractCostNet",
       "weight": 1.0
      },
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 6.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      }
     },
     "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": "Deferred contract acquisition costs \u2014 less current portion",
        "verboseLabel": "Deferred contract acquisition costs, non-current"
       }
      }
     },
     "localname": "CapitalizedContractCostNetNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CashAndCashEquivalentsAtCarryingValue": {
     "auth_ref": [
      "r1",
      "r28",
      "r95"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 1.0,
       "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",
        "verboseLabel": "Cash and cash equivalents"
       }
      }
     },
     "localname": "CashAndCashEquivalentsAtCarryingValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CashAndCashEquivalentsAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of cash and cash equivalent balance.",
        "label": "Cash and Cash Equivalents [Axis]",
        "terseLabel": "Cash and Cash Equivalents [Axis]"
       }
      }
     },
     "localname": "CashAndCashEquivalentsAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CashAndCashEquivalentsFairValueDisclosure": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Fair value portion 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.",
        "label": "Cash and Cash Equivalents, Fair Value Disclosure",
        "terseLabel": "Cash equivalents"
       }
      }
     },
     "localname": "CashAndCashEquivalentsFairValueDisclosure",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CashAndCashEquivalentsLineItems": {
     "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": "Cash and Cash Equivalents [Line Items]",
        "terseLabel": "Cash and Cash Equivalents"
       }
      }
     },
     "localname": "CashAndCashEquivalentsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Cash and Cash Equivalents, Period Increase (Decrease) [Abstract]",
        "terseLabel": "Cash and cash equivalents:"
       }
      }
     },
     "localname": "CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CashAndCashEquivalentsPolicyTextBlock": {
     "auth_ref": [
      "r8",
      "r96",
      "r103"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for cash and cash equivalents, including the policy for determining which items are treated as cash equivalents. Other information that may be disclosed includes (1) the nature of any restrictions on the entity's use of its cash and cash equivalents, (2) whether the entity's cash and cash equivalents are insured or expose the entity to credit risk, (3) the classification of any negative balance accounts (overdrafts), and (4) the carrying basis of cash equivalents (for example, at cost) and whether the carrying amount of cash equivalents approximates fair value.",
        "label": "Cash and Cash Equivalents, Policy [Policy Text Block]",
        "terseLabel": "Cash and Cash Equivalents"
       }
      }
     },
     "localname": "CashAndCashEquivalentsPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents": {
     "auth_ref": [
      "r88",
      "r95",
      "r101"
     ],
     "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": "End of year",
        "periodStartLabel": "Beginning of year"
       }
      }
     },
     "localname": "CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect": {
     "auth_ref": [
      "r88",
      "r393"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "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 increase (decrease) in cash and cash equivalents"
       }
      }
     },
     "localname": "CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CashFlowOperatingActivitiesLesseeAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Cash Flow, Operating Activities, Lessee [Abstract]",
        "terseLabel": "Cash paid for amounts included in the measurement of lease liabilities:"
       }
      }
     },
     "localname": "CashFlowOperatingActivitiesLesseeAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CashMember": {
     "auth_ref": [
      "r8"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "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.",
        "label": "Cash [Member]",
        "terseLabel": "Cash"
       }
      }
     },
     "localname": "CashMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CashUninsuredAmount": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.",
        "label": "Cash, Uninsured Amount",
        "terseLabel": "Cash, uninsured amount"
       }
      }
     },
     "localname": "CashUninsuredAmount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesConcentrationRisksDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CertificatesOfDepositMember": {
     "auth_ref": [
      "r446"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Short to medium-term investment available at banks and savings and loan institutions where a customer agrees to lend money to the institution for a certain amount of time and is paid a predetermined rate of interest. Certificates of deposit (CD) are typically Federal Deposit Insurance Corporation (FDIC) insured.",
        "label": "Certificates of Deposit [Member]",
        "terseLabel": "Certificates of deposit"
       }
      }
     },
     "localname": "CertificatesOfDepositMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ChangeInAccountingEstimateByTypeAxis": {
     "auth_ref": [
      "r114",
      "r118",
      "r135",
      "r137"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of change in accounting estimate.",
        "label": "Change in Accounting Estimate by Type [Axis]",
        "terseLabel": "Change in Accounting Estimate by Type [Axis]"
       }
      }
     },
     "localname": "ChangeInAccountingEstimateByTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ChangeInAccountingEstimateTypeDomain": {
     "auth_ref": [
      "r114",
      "r118",
      "r135",
      "r138"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Identification of the accounting estimate that was changed that had the effect of adjusting the carrying amount of an existing asset or liability, or that will alter the subsequent accounting for existing or future assets or liabilities.",
        "label": "Change in Accounting Estimate, Type [Domain]",
        "terseLabel": "Change in Accounting Estimate, Type [Domain]"
       }
      }
     },
     "localname": "ChangeInAccountingEstimateTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ClassOfStockDomain": {
     "auth_ref": [],
     "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 [Domain]"
       }
      }
     },
     "localname": "ClassOfStockDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails",
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails",
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_CommercialPaperMember": {
     "auth_ref": [
      "r235"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Unsecured promissory note (generally negotiable) that provides institutions with short-term funds.",
        "label": "Commercial Paper [Member]",
        "terseLabel": "Commercial paper"
       }
      }
     },
     "localname": "CommercialPaperMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CommissionsPolicy": {
     "auth_ref": [
      "r103",
      "r430",
      "r431"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for fees earned by the broker dealer, acting as an agent in the buying and selling of securities and administrative efforts on behalf of customers and may include the timing of commission revenue recognition and presentation in the financial statements. Commissions earned are usually related to the broker dealer's customers' trading volume and the dollar amounts of the trades.",
        "label": "Commissions, Policy [Policy Text Block]",
        "terseLabel": "Commissions"
       }
      }
     },
     "localname": "CommissionsPolicy",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_CommitmentsAndContingencies": {
     "auth_ref": [
      "r42",
      "r220",
      "r439",
      "r457"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 3.0,
       "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 (Note 10)"
       }
      }
     },
     "localname": "CommitmentsAndContingencies",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CommitmentsAndContingenciesDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Commitments and Contingencies Disclosure [Abstract]",
        "terseLabel": "Commitments and Contingencies Disclosure [Abstract]"
       }
      }
     },
     "localname": "CommitmentsAndContingenciesDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_CommitmentsAndContingenciesDisclosureTextBlock": {
     "auth_ref": [
      "r219",
      "r229"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingencies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_CommonStockCapitalSharesReservedForFutureIssuance": {
     "auth_ref": [
      "r44"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Aggregate number of common shares reserved for future issuance.",
        "label": "Common Stock, Capital Shares Reserved for Future Issuance",
        "terseLabel": "Shares of common stock reserved for future issuance (in shares)"
       }
      }
     },
     "localname": "CommonStockCapitalSharesReservedForFutureIssuance",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_CommonStockMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Stock that is subordinate to all other stock of the issuer.",
        "label": "Common Stock [Member]",
        "terseLabel": "Common Stock"
       }
      }
     },
     "localname": "CommonStockMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CommonStockParOrStatedValuePerShare": {
     "auth_ref": [
      "r18"
     ],
     "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 (in USD per share)"
       }
      }
     },
     "localname": "CommonStockParOrStatedValuePerShare",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_CommonStockSharesAuthorized": {
     "auth_ref": [
      "r18"
     ],
     "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 (in shares)"
       }
      }
     },
     "localname": "CommonStockSharesAuthorized",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_CommonStockSharesIssued": {
     "auth_ref": [
      "r18"
     ],
     "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",
        "verboseLabel": "Common stock, shares issued (in shares)"
       }
      }
     },
     "localname": "CommonStockSharesIssued",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_CommonStockSharesOutstanding": {
     "auth_ref": [
      "r18",
      "r249"
     ],
     "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",
        "terseLabel": "Common stock, shares outstanding (in shares)"
       }
      }
     },
     "localname": "CommonStockSharesOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_CommonStockValueOutstanding": {
     "auth_ref": [
      "r18"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_StockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Value of all classes of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares exclude common shares repurchased by the entity and held as treasury shares.",
        "label": "Common Stock, Value, Outstanding",
        "terseLabel": "Common stock, $0.001 par value; 450,000 shares authorized, 61,544 shares and 59,210 shares issued and outstanding as of December 31, 2019 and 2018, respectively"
       }
      }
     },
     "localname": "CommonStockValueOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CompensationAndRetirementDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Retirement Benefits [Abstract]",
        "terseLabel": "Retirement Benefits [Abstract]"
       }
      }
     },
     "localname": "CompensationAndRetirementDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_CompensationRelatedCostsPolicyTextBlock": {
     "auth_ref": [
      "r102",
      "r286"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for salaries, bonuses, incentive awards, postretirement and postemployment benefits granted to employees, including equity-based arrangements; discloses methodologies for measurement, and the bases for recognizing related assets and liabilities and recognizing and reporting compensation expense.",
        "label": "Compensation Related Costs, Policy [Policy Text Block]",
        "terseLabel": "Stock-Based Compensation"
       }
      }
     },
     "localname": "CompensationRelatedCostsPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ComprehensiveIncomeNetOfTax": {
     "auth_ref": [
      "r57",
      "r59",
      "r60"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ComprehensiveIncomePolicyPolicyTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for comprehensive income.",
        "label": "Comprehensive Income, Policy [Policy Text Block]",
        "terseLabel": "Comprehensive income (loss)"
       }
      }
     },
     "localname": "ComprehensiveIncomePolicyPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ComputerEquipmentMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Long lived, depreciable assets that are used in the creation, maintenance and utilization of information systems.",
        "label": "Computer Equipment [Member]",
        "terseLabel": "Computer and network equipment"
       }
      }
     },
     "localname": "ComputerEquipmentMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ComputerSoftwareIntangibleAssetMember": {
     "auth_ref": [
      "r199",
      "r204",
      "r370"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Collection of computer programs and related data that provide instructions to a computer, for example, but not limited to, application program, control module or operating system, that perform one or more particular functions or tasks.",
        "label": "Computer Software, Intangible Asset [Member]",
        "terseLabel": "Computer software"
       }
      }
     },
     "localname": "ComputerSoftwareIntangibleAssetMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ConcentrationRiskCreditRisk": {
     "auth_ref": [
      "r143",
      "r449"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for credit risk.",
        "label": "Concentration Risk, Credit Risk, Policy [Policy Text Block]",
        "terseLabel": "Concentration Risks"
       }
      }
     },
     "localname": "ConcentrationRiskCreditRisk",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ContingentConsiderationByTypeAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of contingent consideration.",
        "label": "Contingent Consideration by Type [Axis]",
        "terseLabel": "Contingent Consideration by Type [Axis]"
       }
      }
     },
     "localname": "ContingentConsiderationByTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ContingentConsiderationTypeDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Description of contingent payment arrangement.",
        "label": "Contingent Consideration Type [Domain]",
        "terseLabel": "Contingent Consideration Type [Domain]"
       }
      }
     },
     "localname": "ContingentConsiderationTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock": {
     "auth_ref": [
      "r262"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of contract balances and changes in contract balances.",
        "label": "Contract with Customer, Asset and Liability [Table Text Block]",
        "terseLabel": "Contract with customer, asset and liability"
       }
      }
     },
     "localname": "ContractWithCustomerAssetAndLiabilityTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RevenueTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ContractWithCustomerAssetNetCurrent": {
     "auth_ref": [
      "r259",
      "r261",
      "r266"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails": {
       "order": 1.0,
       "parentTag": "fivn_ContractwithCustomerAssetLiabilityNet",
       "weight": 1.0
      },
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails": {
       "order": 3.0,
       "parentTag": "us-gaap_PrepaidExpenseAndOtherAssetsCurrent",
       "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, Net, Current",
        "terseLabel": "Contract assets (included in prepaid expenses and other current assets)"
       }
      }
     },
     "localname": "ContractWithCustomerAssetNetCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ContractWithCustomerLiabilityCurrent": {
     "auth_ref": [
      "r259",
      "r260",
      "r266"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails": {
       "order": 2.0,
       "parentTag": "fivn_ContractwithCustomerAssetLiabilityNet",
       "weight": -1.0
      },
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 4.0,
       "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",
        "verboseLabel": "Contract liabilities (deferred revenue)"
       }
      }
     },
     "localname": "ContractWithCustomerLiabilityCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC606AdoptionImpactandRevenuefromContractswithCustomersContractBalancesDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ContractWithCustomerLiabilityRevenueRecognized": {
     "auth_ref": [
      "r267"
     ],
     "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": "Contract revenue recognized"
       }
      }
     },
     "localname": "ContractWithCustomerLiabilityRevenueRecognized",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RevenueNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ConvertibleDebtMember": {
     "auth_ref": [
      "r238"
     ],
     "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": "Convertible debt"
       }
      }
     },
     "localname": "ConvertibleDebtMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlowsParenthetical",
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ConvertibleDebtNoncurrent": {
     "auth_ref": [
      "r40"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_Liabilities",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.",
        "label": "Convertible Debt, Noncurrent",
        "terseLabel": "Convertible senior notes"
       }
      }
     },
     "localname": "ConvertibleDebtNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ConvertibleDebtTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of borrowings which can be exchanged for a specified number of another security at the option of the issuer or the holder. Disclosures include, but are not limited to, principal amount, amortized premium or discount, and amount of liability and equity components.",
        "label": "Convertible Debt [Table Text Block]",
        "terseLabel": "Schedule of net carrying amount of the liability component of the notes"
       }
      }
     },
     "localname": "ConvertibleDebtTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_CorporateBondSecuritiesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "This category includes information about long-term debt securities that are issued by either a domestic or foreign corporate business entity with a date certain promise of repayment and a return to the holder for the time value of money (for example, variable or fixed interest, original issue discount).",
        "label": "Corporate Bond Securities [Member]",
        "terseLabel": "Corporate bonds"
       }
      }
     },
     "localname": "CorporateBondSecuritiesMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CostOfRevenue": {
     "auth_ref": [
      "r73"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 2.0,
       "parentTag": "us-gaap_GrossProfit",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The aggregate cost of goods produced and sold and services rendered during the reporting period.",
        "label": "Cost of Revenue",
        "terseLabel": "Cost of revenue"
       }
      }
     },
     "localname": "CostOfRevenue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "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"
       }
      }
     },
     "localname": "CostOfSalesMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "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 [Axis]"
       }
      }
     },
     "localname": "CreditFacilityAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "CreditFacilityDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.",
        "label": "Cumulative Effect of New Accounting Principle in Period of Adoption",
        "terseLabel": "Effect on financial statements"
       }
      }
     },
     "localname": "CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CurrentFederalTaxExpenseBenefit": {
     "auth_ref": [
      "r106",
      "r358",
      "r363"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.",
        "label": "Current Federal Tax Expense (Benefit)",
        "terseLabel": "U.S. federal"
       }
      }
     },
     "localname": "CurrentFederalTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CurrentForeignTaxExpenseBenefit": {
     "auth_ref": [
      "r111",
      "r359"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails": {
       "order": 3.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "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": "Foreign"
       }
      }
     },
     "localname": "CurrentForeignTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_CurrentStateAndLocalTaxExpenseBenefit": {
     "auth_ref": [
      "r106",
      "r358",
      "r363"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_IncomeTaxExpenseBenefit",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.",
        "label": "Current State and Local Tax Expense (Benefit)",
        "terseLabel": "U.S. state"
       }
      }
     },
     "localname": "CurrentStateAndLocalTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Debt Disclosure [Abstract]",
        "terseLabel": "Debt Disclosure [Abstract]"
       }
      }
     },
     "localname": "DebtDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtDisclosureTextBlock": {
     "auth_ref": [
      "r245"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_DebtInstrumentAxis": {
     "auth_ref": [
      "r11",
      "r12",
      "r13",
      "r433",
      "r435",
      "r451"
     ],
     "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 [Axis]"
       }
      }
     },
     "localname": "DebtInstrumentAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails",
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "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"
       }
      }
     },
     "localname": "DebtInstrumentBasisSpreadOnVariableRate1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_DebtInstrumentCarryingAmount": {
     "auth_ref": [
      "r13",
      "r240",
      "r435",
      "r451"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofMaturitiesofDebtDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_LongTermDebt",
       "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",
        "terseLabel": "Principal",
        "totalLabel": "Total",
        "verboseLabel": "Promissory note payable"
       }
      }
     },
     "localname": "DebtInstrumentCarryingAmount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesCommitmentsandLeasesDetails",
      "http://www.five9.com/role/DebtScheduleofMaturitiesofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent": {
     "auth_ref": [
      "r239"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "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",
        "totalLabel": "Net carrying amount"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentConvertibleConversionPrice1": {
     "auth_ref": [
      "r242"
     ],
     "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": "Conversion price on convertible debt (in USD per share)"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleConversionPrice1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_DebtInstrumentConvertibleConversionRatio1": {
     "auth_ref": [
      "r39",
      "r250",
      "r253",
      "r255"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.",
        "label": "Debt Instrument, Convertible, Conversion Ratio",
        "terseLabel": "Conversion ratio on convertible debt"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleConversionRatio1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "pureItemType"
    },
    "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": "Number of consecutive trading days"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleThresholdConsecutiveTradingDays1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "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": "Threshold percentage of stock price trigger"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "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": "Number of trading days"
       }
      }
     },
     "localname": "DebtInstrumentConvertibleThresholdTradingDays",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "integerItemType"
    },
    "us-gaap_DebtInstrumentInterestRateEffectivePercentage": {
     "auth_ref": [
      "r38",
      "r243",
      "r397"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.",
        "label": "Debt Instrument, Interest Rate, Effective Percentage",
        "terseLabel": "Effective interest rate on debt"
       }
      }
     },
     "localname": "DebtInstrumentInterestRateEffectivePercentage",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_DebtInstrumentInterestRateStatedPercentage": {
     "auth_ref": [
      "r38"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Contractual interest rate for funds borrowed, under the debt agreement.",
        "label": "Debt Instrument, Interest Rate, Stated Percentage",
        "terseLabel": "Stated interest rate on debt"
       }
      }
     },
     "localname": "DebtInstrumentInterestRateStatedPercentage",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentNameDomain": {
     "auth_ref": [
      "r40"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "DebtInstrumentNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails",
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DebtInstrumentRedemptionPeriodAxis": {
     "auth_ref": [
      "r447"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information about timing of debt redemption features under terms of the debt agreement.",
        "label": "Debt Instrument, Redemption, Period [Axis]",
        "terseLabel": "Debt Instrument, Redemption, Period [Axis]"
       }
      }
     },
     "localname": "DebtInstrumentRedemptionPeriodAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentRedemptionPeriodDomain": {
     "auth_ref": [
      "r447"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Period as defined under terms of the debt agreement for debt redemption features.",
        "label": "Debt Instrument, Redemption, Period [Domain]",
        "terseLabel": "Debt Instrument, Redemption, Period [Domain]"
       }
      }
     },
     "localname": "DebtInstrumentRedemptionPeriodDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DebtInstrumentRedemptionPeriodOneMember": {
     "auth_ref": [
      "r447"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Period one representing most current period of debt redemption features under terms of the debt agreement.",
        "label": "Debt Instrument, Redemption, Period One [Member]",
        "terseLabel": "Fundamental change event"
       }
      }
     },
     "localname": "DebtInstrumentRedemptionPeriodOneMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DebtInstrumentRedemptionPeriodTwoMember": {
     "auth_ref": [
      "r447"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Period two representing second most current period of debt redemption features under terms of the debt agreement.",
        "label": "Debt Instrument, Redemption, Period Two [Member]",
        "terseLabel": "On or after May 5, 2021"
       }
      }
     },
     "localname": "DebtInstrumentRedemptionPeriodTwoMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DebtInstrumentRedemptionPricePercentage": {
     "auth_ref": [
      "r447"
     ],
     "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 redemption price as percentage of principal amount"
       }
      }
     },
     "localname": "DebtInstrumentRedemptionPricePercentage",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_DebtInstrumentSinkingFundPayment": {
     "auth_ref": [
      "r250"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount paid into a fund, which is used to retire the debt instrument.",
        "label": "Debt Instrument, Sinking Fund Payment",
        "terseLabel": "Sinking fund payment"
       }
      }
     },
     "localname": "DebtInstrumentSinkingFundPayment",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtInstrumentTable": {
     "auth_ref": [
      "r40",
      "r108",
      "r250",
      "r254",
      "r255",
      "r256",
      "r396",
      "r397",
      "r399",
      "r448"
     ],
     "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": "Schedule of Long-term Debt Instruments [Table]"
       }
      }
     },
     "localname": "DebtInstrumentTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtInstrumentUnamortizedDiscount": {
     "auth_ref": [
      "r396",
      "r399"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_LongTermDebt",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount, after accumulated amortization, of debt discount.",
        "label": "Debt Instrument, Unamortized Discount",
        "negatedLabel": "Debt Instrument, Unamortized Discount"
       }
      }
     },
     "localname": "DebtInstrumentUnamortizedDiscount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss": {
     "auth_ref": [
      "r171",
      "r185"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.",
        "label": "Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss",
        "negatedTerseLabel": "Gross Unrealized Losses"
       }
      }
     },
     "localname": "DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DebtSecuritiesAvailableForSaleTable": {
     "auth_ref": [
      "r172"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of information about investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).",
        "label": "Debt Securities, Available-for-sale [Table]",
        "terseLabel": "Debt Securities, Available-for-sale [Table]"
       }
      }
     },
     "localname": "DebtSecuritiesAvailableForSaleTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DebtSecuritiesAvailableForSaleTableTextBlock": {
     "auth_ref": [
      "r172"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).",
        "label": "Debt Securities, Available-for-sale [Table Text Block]",
        "terseLabel": "Schedule of marketable investments"
       }
      }
     },
     "localname": "DebtSecuritiesAvailableForSaleTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss": {
     "auth_ref": [
      "r170",
      "r183"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.",
        "label": "Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss",
        "terseLabel": "Fair Value"
       }
      }
     },
     "localname": "DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock": {
     "auth_ref": [
      "r32"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of the amounts paid in advance for capitalized costs that will be expensed with the passage of time or the occurrence of a triggering event, and will be charged against earnings within one year or the normal operating cycle, if longer; the aggregate carrying amount of current assets, not separately presented elsewhere in the balance sheet; and other deferred costs.",
        "label": "Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]",
        "terseLabel": "Schedule of prepaid expenses and other current assets"
       }
      }
     },
     "localname": "DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_DeferredFinanceCostsGross": {
     "auth_ref": [
      "r398"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails": {
       "order": 3.0,
       "parentTag": "us-gaap_LongTermDebt",
       "weight": -1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.",
        "label": "Debt Issuance Costs, Gross",
        "negatedTerseLabel": "Unamortized issuance costs",
        "verboseLabel": "Debt issuance costs"
       }
      }
     },
     "localname": "DeferredFinanceCostsGross",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredIncomeTaxLiabilities": {
     "auth_ref": [
      "r14",
      "r15",
      "r348",
      "r434",
      "r450"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_DeferredTaxAssetsLiabilitiesNet",
       "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",
        "negatedTotalLabel": "Gross deferred tax liabilities"
       }
      }
     },
     "localname": "DeferredIncomeTaxLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredRentCredit": {
     "auth_ref": [
      "r400"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.",
        "label": "Deferred Rent Credit",
        "negatedTerseLabel": "Reversal of deferred rent"
       }
      }
     },
     "localname": "DeferredRentCredit",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsDeferredIncome": {
     "auth_ref": [
      "r334",
      "r356",
      "r357"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "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 deferred income.",
        "label": "Deferred Tax Assets, Deferred Income",
        "terseLabel": "Deferred revenue"
       }
      }
     },
     "localname": "DeferredTaxAssetsDeferredIncome",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 6.0,
       "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 intangible assets including goodwill.",
        "label": "Deferred Tax Assets, Goodwill and Intangible Assets",
        "terseLabel": "Intangibles"
       }
      }
     },
     "localname": "DeferredTaxAssetsGoodwillAndIntangibleAssets",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsGross": {
     "auth_ref": [
      "r349"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 1.0,
       "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",
        "terseLabel": "Deferred tax asset",
        "totalLabel": "Gross deferred tax assets"
       }
      }
     },
     "localname": "DeferredTaxAssetsGross",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails",
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsGrossAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Deferred Tax Assets, Gross [Abstract]",
        "terseLabel": "Deferred tax assets:"
       }
      }
     },
     "localname": "DeferredTaxAssetsGrossAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DeferredTaxAssetsLiabilitiesNet": {
     "auth_ref": [
      "r352"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "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, without jurisdictional netting.",
        "label": "Deferred Tax Assets, Net",
        "totalLabel": "Net deferred taxes"
       }
      }
     },
     "localname": "DeferredTaxAssetsLiabilitiesNet",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsNet": {
     "auth_ref": [
      "r350"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_DeferredTaxAssetsLiabilitiesNet",
       "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",
        "totalLabel": "Net deferred tax assets"
       }
      }
     },
     "localname": "DeferredTaxAssetsNet",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits": {
     "auth_ref": [
      "r333",
      "r356",
      "r357"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 5.0,
       "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 compensation and benefits costs.",
        "label": "Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits",
        "terseLabel": "Accrued compensation"
       }
      }
     },
     "localname": "DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities": {
     "auth_ref": [
      "r333",
      "r356",
      "r357"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 2.0,
       "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 accrued liabilities.",
        "label": "Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities",
        "terseLabel": "Accrued liabilities"
       }
      }
     },
     "localname": "DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts": {
     "auth_ref": [
      "r333",
      "r356",
      "r357"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "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 the allowance for doubtful accounts.",
        "label": "Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts",
        "terseLabel": "Allowance for doubtful accounts"
       }
      }
     },
     "localname": "DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxAssetsValuationAllowance": {
     "auth_ref": [
      "r351"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 2.0,
       "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",
        "negatedTerseLabel": "Valuation allowance",
        "terseLabel": "Deferred tax asset, valuation allowance"
       }
      }
     },
     "localname": "DeferredTaxAssetsValuationAllowance",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails",
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_DeferredTaxLiabilitiesFinancingArrangements": {
     "auth_ref": [
      "r334",
      "r356",
      "r357"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "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 financing arrangements.",
        "label": "Deferred Tax Liabilities, Financing Arrangements",
        "negatedTerseLabel": "Convertible senior notes"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesFinancingArrangements",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets": {
     "auth_ref": [
      "r334",
      "r356",
      "r357"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 2.0,
       "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 intangible assets other than goodwill.",
        "label": "Deferred Tax Liabilities, Intangible Assets",
        "negatedTerseLabel": "Amortized intangibles"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxLiabilitiesOther": {
     "auth_ref": [
      "r334",
      "r356",
      "r357"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 4.0,
       "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",
        "negatedLabel": "Other"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesOther",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment": {
     "auth_ref": [
      "r334",
      "r356",
      "r357"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails": {
       "order": 1.0,
       "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 property, plant, and equipment.",
        "label": "Deferred Tax Liabilities, Property, Plant and Equipment",
        "negatedTerseLabel": "Property and equipment"
       }
      }
     },
     "localname": "DeferredTaxLiabilitiesPropertyPlantAndEquipment",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation": {
     "auth_ref": [
      "r273"
     ],
     "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": "Defined benefit liability"
       }
      }
     },
     "localname": "DefinedBenefitPlanAccumulatedBenefitObligation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RetirementPlansDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DefinedContributionPlanCostRecognized": {
     "auth_ref": [
      "r275"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of cost for defined contribution plan.",
        "label": "Defined Contribution Plan, Cost",
        "terseLabel": "Contribution expense"
       }
      }
     },
     "localname": "DefinedContributionPlanCostRecognized",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RetirementPlansDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_Depreciation": {
     "auth_ref": [
      "r93",
      "r211"
     ],
     "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 and amortization of property and equipment"
       }
      }
     },
     "localname": "Depreciation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DepreciationDepletionAndAmortization": {
     "auth_ref": [
      "r93",
      "r151"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "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",
        "terseLabel": "Depreciation and amortization",
        "verboseLabel": "Total depreciation and amortization"
       }
      }
     },
     "localname": "DepreciationDepletionAndAmortization",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_DevelopedTechnologyRightsMember": {
     "auth_ref": [
      "r371"
     ],
     "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": "iPaaS Platform",
        "verboseLabel": "Developed technology"
       }
      }
     },
     "localname": "DevelopedTechnologyRightsMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails",
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_DomesticCountryMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Designated tax department of the government that is entitled to levy and collect income taxes from the entity in its country of domicile.",
        "label": "Domestic Tax Authority [Member]",
        "terseLabel": "Federal"
       }
      }
     },
     "localname": "DomesticCountryMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_EarningsPerShareAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Earnings Per Share [Abstract]",
        "terseLabel": "Earnings Per Share [Abstract]"
       }
      }
     },
     "localname": "EarningsPerShareAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_EarningsPerShareBasic": {
     "auth_ref": [
      "r67",
      "r116",
      "r124",
      "r125",
      "r126",
      "r127",
      "r131",
      "r443",
      "r460"
     ],
     "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": "Basic (in USD per share)"
       }
      }
     },
     "localname": "EarningsPerShareBasic",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_EarningsPerShareBasicAndDiluted": {
     "auth_ref": [
      "r126"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements.  Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period.  Diluted earnings per share includes the amount of net income or 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, Basic and Diluted",
        "terseLabel": "Basic and diluted (in USD per share)"
       }
      }
     },
     "localname": "EarningsPerShareBasicAndDiluted",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareBasicandDilutedNetLossPerShareDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_EarningsPerShareBasicAndDilutedAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Earnings Per Share, Basic and Diluted [Abstract]",
        "terseLabel": "Net loss per share:",
        "verboseLabel": "Net income (loss) per share:"
       }
      }
     },
     "localname": "EarningsPerShareBasicAndDilutedAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_EarningsPerShareBasicAndDilutedOtherDisclosuresAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract]",
        "terseLabel": "Shares used in computing net loss per share:"
       }
      }
     },
     "localname": "EarningsPerShareBasicAndDilutedOtherDisclosuresAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_EarningsPerShareDiluted": {
     "auth_ref": [
      "r67",
      "r116",
      "r124",
      "r125",
      "r126",
      "r127",
      "r131",
      "r443",
      "r460"
     ],
     "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": "Diluted (in USD per share)"
       }
      }
     },
     "localname": "EarningsPerShareDiluted",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_EarningsPerSharePolicyTextBlock": {
     "auth_ref": [
      "r103",
      "r128",
      "r129",
      "r130"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for computing basic and diluted earnings or loss per share for each class of common stock and participating security. Addresses all significant policy factors, including any antidilutive items that have been excluded from the computation and takes into account stock dividends, splits and reverse splits that occur after the balance sheet date of the latest reporting period but before the issuance of the financial statements.",
        "label": "Earnings Per Share, Policy [Policy Text Block]",
        "terseLabel": "Net Income (Loss) Per Share"
       }
      }
     },
     "localname": "EarningsPerSharePolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_EarningsPerShareTextBlock": {
     "auth_ref": [
      "r132"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShare"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate": {
     "auth_ref": [
      "r339",
      "r340",
      "r362"
     ],
     "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 income tax rate (percent)"
       }
      }
     },
     "localname": "EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Amount": {
     "auth_ref": [
      "r339"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "order": 6.0,
       "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": "Impact of 2017 Tax Act"
       }
      }
     },
     "localname": "EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Amount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_EmployeeRelatedLiabilitiesCurrent": {
     "auth_ref": [
      "r36"
     ],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccruedandOtherCurrentLiabilitiesDetails": {
       "order": 2.0,
       "parentTag": "fivn_AccruedLiabilitiesandOtherCurrentLiabilities",
       "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"
       }
      }
     },
     "localname": "EmployeeRelatedLiabilitiesCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccruedandOtherCurrentLiabilitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "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": "Stock-based Compensation Expense"
       }
      }
     },
     "localname": "EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized": {
     "auth_ref": [
      "r312"
     ],
     "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": "Unrecognized stock-based compensation expense"
       }
      }
     },
     "localname": "EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1": {
     "auth_ref": [
      "r312"
     ],
     "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 amortization period"
       }
      }
     },
     "localname": "EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_EmployeeStockMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "An Employee Stock Purchase Plan is a tax-efficient means by which employees of a corporation can purchase the corporation's stock.",
        "label": "Employee Stock [Member]",
        "terseLabel": "Shares available for future issuance under ESPP",
        "verboseLabel": "ESPP"
       }
      }
     },
     "localname": "EmployeeStockMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityESPPDetails",
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_EmployeeStockOptionMember": {
     "auth_ref": [
      "r309"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Share-based payment arrangement granting right, subject to vesting and other restrictions, to purchase or sell certain number of shares at predetermined price for specified period of time.",
        "label": "Share-based Payment Arrangement, Option [Member]",
        "terseLabel": "Stock options outstanding"
       }
      }
     },
     "localname": "EmployeeStockOptionMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails",
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails",
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails",
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_EmploymentContractsMember": {
     "auth_ref": [
      "r369"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Contracts securing the services of employees, which may define the period of employment and the nature of the business relationship, and which may include nondisclosure and noncompete restrictions.",
        "label": "Employment Contracts [Member]",
        "terseLabel": "Acquired workforce"
       }
      }
     },
     "localname": "EmploymentContractsMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails",
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_EquityAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Equity [Abstract]",
        "terseLabel": "Equity [Abstract]"
       }
      }
     },
     "localname": "EquityAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_EquityComponentDomain": {
     "auth_ref": [
      "r249"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "EquityComponentDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems": {
     "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, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]",
        "terseLabel": "Fair Value Measurements Measured on a Recurring Basis"
       }
      }
     },
     "localname": "FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable": {
     "auth_ref": [
      "r383",
      "r384",
      "r385",
      "r389"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of information about asset and liability measured at fair value on recurring and nonrecurring basis.",
        "label": "Fair Value, Recurring and Nonrecurring [Table]",
        "terseLabel": "Fair value measurements, recurring"
       }
      }
     },
     "localname": "FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueByBalanceSheetGroupingTextBlock": {
     "auth_ref": [
      "r383",
      "r391"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of 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 Text Block]",
        "terseLabel": "Schedule of assets carried at fair value"
       }
      }
     },
     "localname": "FairValueByBalanceSheetGroupingTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_FairValueByFairValueHierarchyLevelAxis": {
     "auth_ref": [
      "r271",
      "r272",
      "r274",
      "r384",
      "r423"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by level within fair value hierarchy and fair value measured at net asset value per share as practical expedient.",
        "label": "Fair Value Hierarchy and NAV [Axis]",
        "terseLabel": "Fair Value Hierarchy and NAV [Axis]"
       }
      }
     },
     "localname": "FairValueByFairValueHierarchyLevelAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueByMeasurementFrequencyAxis": {
     "auth_ref": [
      "r383",
      "r384",
      "r386",
      "r387",
      "r390"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by measurement frequency.",
        "label": "Measurement Frequency [Axis]",
        "terseLabel": "Measurement Frequency [Axis]"
       }
      }
     },
     "localname": "FairValueByMeasurementFrequencyAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueDisclosuresAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Fair Value Disclosures [Abstract]",
        "terseLabel": "Fair Value Disclosures [Abstract]"
       }
      }
     },
     "localname": "FairValueDisclosuresAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_FairValueInputsLevel1Member": {
     "auth_ref": [
      "r271",
      "r272",
      "r274",
      "r384",
      "r424"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Quoted prices in active markets for identical assets or liabilities that the reporting entity can access at the measurement date.",
        "label": "Fair Value, Inputs, Level 1 [Member]",
        "terseLabel": "Level 1"
       }
      }
     },
     "localname": "FairValueInputsLevel1Member",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FairValueInputsLevel2Member": {
     "auth_ref": [
      "r271",
      "r272",
      "r274",
      "r384",
      "r425"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Inputs other than quoted prices included within level 1 that are observable for an asset or liability, either directly or indirectly, including, but not limited to, quoted prices for similar assets or liabilities in active markets, or quoted prices for identical or similar assets or liabilities in inactive markets.",
        "label": "Fair Value, Inputs, Level 2 [Member]",
        "terseLabel": "Level 2"
       }
      }
     },
     "localname": "FairValueInputsLevel2Member",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FairValueInputsLevel3Member": {
     "auth_ref": [
      "r271",
      "r272",
      "r274",
      "r384",
      "r426"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.",
        "label": "Fair Value, Inputs, Level 3 [Member]",
        "terseLabel": "Level 3"
       }
      }
     },
     "localname": "FairValueInputsLevel3Member",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FairValueMeasurementFrequencyDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Measurement frequency.",
        "label": "Measurement Frequency [Domain]",
        "terseLabel": "Fair Value, Measurement Frequency [Domain]"
       }
      }
     },
     "localname": "FairValueMeasurementFrequencyDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FairValueMeasurementsFairValueHierarchyDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Categories used to prioritize the inputs to valuation techniques to measure fair value.",
        "label": "Fair Value Hierarchy and NAV [Domain]",
        "terseLabel": "Fair Value Hierarchy and NAV [Domain]"
       }
      }
     },
     "localname": "FairValueMeasurementsFairValueHierarchyDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FairValueMeasurementsNonrecurringMember": {
     "auth_ref": [
      "r383",
      "r384",
      "r386",
      "r387",
      "r388",
      "r390"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Infrequent fair value measurement. Includes, but is not limited to, fair value adjustment for impairment of asset, liability or equity, not frequently measured at fair value.",
        "label": "Fair Value, Nonrecurring [Member]",
        "terseLabel": "Nonrecurring"
       }
      }
     },
     "localname": "FairValueMeasurementsNonrecurringMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FinanceLeaseInterestExpense": {
     "auth_ref": [
      "r404",
      "r410",
      "r418"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails": {
       "order": 2.0,
       "parentTag": "fivn_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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilitiesPaymentsDueAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Finance Lease, Liability, Payment, Due [Abstract]",
        "terseLabel": "Finance Leases"
       }
      }
     },
     "localname": "FinanceLeaseLiabilitiesPaymentsDueAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FinanceLeaseLiability": {
     "auth_ref": [
      "r403",
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_FinanceLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Present value of lessee's discounted obligation for lease payments from finance lease.",
        "label": "Finance Lease, Liability",
        "terseLabel": "Total",
        "totalLabel": "Total finance lease liabilities"
       }
      }
     },
     "localname": "FinanceLeaseLiability",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityCurrent": {
     "auth_ref": [
      "r403"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_FinanceLeaseLiability",
       "weight": 1.0
      },
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 6.0,
       "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 finance lease, classified as current.",
        "label": "Finance Lease, Liability, Current",
        "terseLabel": "Finance lease liabilities"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityMaturityTableTextBlock": {
     "auth_ref": [
      "r417"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of undiscounted cash flows of finance lease liability. Includes, but is not limited to, reconciliation of undiscounted cash flows to finance lease liability recognized in statement of financial position.",
        "label": "Finance Lease, Liability, Maturity [Table Text Block]",
        "terseLabel": "Schedule of finance lease maturities"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityMaturityTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_FinanceLeaseLiabilityNoncurrent": {
     "auth_ref": [
      "r403"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_FinanceLeaseLiability",
       "weight": 1.0
      },
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 6.0,
       "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 finance lease, classified as noncurrent.",
        "label": "Finance Lease, Liability, Noncurrent",
        "terseLabel": "Finance lease liabilities \u2014 less current portion"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityPaymentsDue": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payments for finance lease.",
        "label": "Finance Lease, Liability, Payment, Due",
        "totalLabel": "Total lease payments"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityPaymentsDue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityPaymentsDueYearFive": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "order": 5.0,
       "parentTag": "us-gaap_FinanceLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fifth fiscal year following latest fiscal year.",
        "label": "Finance Lease, Liability, Payments, Due Year Five",
        "terseLabel": "2024"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityPaymentsDueYearFive",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "order": 4.0,
       "parentTag": "us-gaap_FinanceLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fourth fiscal year following latest fiscal year.",
        "label": "Finance Lease, Liability, Payments, Due Year Four",
        "terseLabel": "2023"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityPaymentsDueYearFour",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "order": 3.0,
       "parentTag": "us-gaap_FinanceLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payments for finance lease, due in third fiscal year following latest fiscal year.",
        "label": "Finance Lease, Liability, Payments, Due Year Three",
        "terseLabel": "2022"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityPaymentsDueYearThree",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "order": 2.0,
       "parentTag": "us-gaap_FinanceLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second fiscal year following latest fiscal year.",
        "label": "Finance Lease, Liability, Payments, Due Year Two",
        "terseLabel": "2021"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityPaymentsDueYearTwo",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "order": 1.0,
       "parentTag": "us-gaap_FinanceLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payments for finance lease, due in remainder of fiscal year following latest fiscal year ended.",
        "label": "Finance Lease, Liability, Payments, Remainder of Fiscal Year",
        "terseLabel": "2020"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_FinanceLeaseLiabilityPaymentsDue",
       "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 finance lease.",
        "label": "Finance Lease, Liability, Undiscounted Excess Amount",
        "negatedLabel": "Less: imputed interest"
       }
      }
     },
     "localname": "FinanceLeaseLiabilityUndiscountedExcessAmount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeasePrincipalPayments": {
     "auth_ref": [
      "r405",
      "r412"
     ],
     "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 used in finance leases"
       }
      }
     },
     "localname": "FinanceLeasePrincipalPayments",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseRightOfUseAssetAmortization": {
     "auth_ref": [
      "r404",
      "r410",
      "r418"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails": {
       "order": 1.0,
       "parentTag": "fivn_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 right-of-use assets"
       }
      }
     },
     "localname": "FinanceLeaseRightOfUseAssetAmortization",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent": {
     "auth_ref": [
      "r415",
      "r418"
     ],
     "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, Finance leases"
       }
      }
     },
     "localname": "FinanceLeaseWeightedAverageDiscountRatePercent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactWeightedAverageRemainingTermsandDiscountRatesDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_FinanceLeaseWeightedAverageRemainingLeaseTerm1": {
     "auth_ref": [
      "r414",
      "r418"
     ],
     "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, Finance leases"
       }
      }
     },
     "localname": "FinanceLeaseWeightedAverageRemainingLeaseTerm1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactWeightedAverageRemainingTermsandDiscountRatesDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_FinancialInstrumentAxis": {
     "auth_ref": [
      "r174",
      "r178",
      "r179",
      "r180",
      "r181",
      "r184",
      "r186",
      "r187",
      "r188"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of financial instrument.",
        "label": "Financial Instrument [Axis]",
        "terseLabel": "Financial Instrument [Axis]"
       }
      }
     },
     "localname": "FinancialInstrumentAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetUsefulLife": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.",
        "label": "Finite-Lived Intangible Asset, Useful Life",
        "terseLabel": "Useful life"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetUsefulLife",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesGoodwillandIntangibleAssetsDetails",
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization": {
     "auth_ref": [
      "r205"
     ],
     "calculation": {
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_FiniteLivedIntangibleAssetsNet",
       "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",
        "negatedTerseLabel": "Accumulated Amortization"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAccumulatedAmortization",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths": {
     "auth_ref": [
      "r207"
     ],
     "calculation": {
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails": {
       "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 during the next fiscal year following the latest fiscal year. Excludes 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 Twelve Months",
        "terseLabel": "2020"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour": {
     "auth_ref": [
      "r207"
     ],
     "calculation": {
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails": {
       "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 during the fourth fiscal year following the latest fiscal year. Excludes 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, Year Four",
        "terseLabel": "2023"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseYearFour",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree": {
     "auth_ref": [
      "r207"
     ],
     "calculation": {
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails": {
       "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 during the third fiscal year following the latest fiscal year. Excludes 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, Year Three",
        "terseLabel": "2022"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseYearThree",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo": {
     "auth_ref": [
      "r207"
     ],
     "calculation": {
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails": {
       "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 during the second fiscal year following the latest fiscal year. Excludes 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, Year Two",
        "terseLabel": "2021"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis": {
     "auth_ref": [
      "r199",
      "r201",
      "r205",
      "r208",
      "r428"
     ],
     "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 [Axis]"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsByMajorClassAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails",
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsGross": {
     "auth_ref": [
      "r205",
      "r428"
     ],
     "calculation": {
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails": {
       "order": 1.0,
       "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"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsGross",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsLineItems": {
     "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": "Finite-Lived Intangible Assets [Line Items]",
        "terseLabel": "Finite-Lived Intangible Assets [Line Items]"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesGoodwillandIntangibleAssetsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain": {
     "auth_ref": [
      "r199",
      "r204"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsMajorClassNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails",
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_FiniteLivedIntangibleAssetsNet": {
     "auth_ref": [
      "r205"
     ],
     "calculation": {
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails": {
       "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",
        "totalLabel": "Total Net Carrying Amount"
       }
      }
     },
     "localname": "FiniteLivedIntangibleAssetsNet",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofExpectedFutureAmortizationExpenseofIntangibleAssetsDetails",
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_FinitelivedIntangibleAssetsAcquired1": {
     "auth_ref": [
      "r200"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.",
        "label": "Finite-lived Intangible Assets Acquired",
        "terseLabel": "Assets acquired"
       }
      }
     },
     "localname": "FinitelivedIntangibleAssetsAcquired1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/AcquisitionofWhenduLLCDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock": {
     "auth_ref": [
      "r103",
      "r392",
      "r394"
     ],
     "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"
       }
      }
     },
     "localname": "ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_FurnitureAndFixturesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.",
        "label": "Furniture and Fixtures [Member]",
        "terseLabel": "Furniture and fixtures"
       }
      }
     },
     "localname": "FurnitureAndFixturesMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_GainLossOnSaleOfInvestments": {
     "auth_ref": [
      "r93"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 7.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.",
        "label": "Gain (Loss) on Sale of Investments",
        "negatedTerseLabel": "Gain on sale of convertible note held for investment"
       }
      }
     },
     "localname": "GainLossOnSaleOfInvestments",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GeneralAndAdministrativeExpense": {
     "auth_ref": [
      "r74"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 3.0,
       "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"
       }
      }
     },
     "localname": "GeneralAndAdministrativeExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GeneralAndAdministrativeExpenseMember": {
     "auth_ref": [
      "r68"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Primary financial statement caption encompassing general and administrative expense.",
        "label": "General and Administrative Expense [Member]",
        "terseLabel": "General and administrative"
       }
      }
     },
     "localname": "GeneralAndAdministrativeExpenseMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_Goodwill": {
     "auth_ref": [
      "r192",
      "r193"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 4.0,
       "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",
        "terseLabel": "Goodwill"
       }
      }
     },
     "localname": "Goodwill",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Goodwill and Intangible Assets Disclosure [Abstract]",
        "terseLabel": "Goodwill and Intangible Assets Disclosure [Abstract]"
       }
      }
     },
     "localname": "GoodwillAndIntangibleAssetsDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock": {
     "auth_ref": [
      "r210"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The entire disclosure for goodwill and intangible assets.",
        "label": "Goodwill and Intangible Assets Disclosure [Text Block]",
        "terseLabel": "Goodwill and Intangible Assets"
       }
      }
     },
     "localname": "GoodwillAndIntangibleAssetsDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssets"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock": {
     "auth_ref": [
      "r103",
      "r196",
      "r202"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for goodwill and intangible assets. This accounting policy also may address how an entity assesses and measures impairment of goodwill and intangible assets.",
        "label": "Goodwill and Intangible Assets, Policy [Policy Text Block]",
        "terseLabel": "Goodwill and Intangible Assets"
       }
      }
     },
     "localname": "GoodwillAndIntangibleAssetsPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_GoodwillImpairedAccumulatedImpairmentLoss": {
     "auth_ref": [
      "r194",
      "r195"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of accumulated impairment loss for 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, Impaired, Accumulated Impairment Loss",
        "terseLabel": "Goodwill impairment, accumulated"
       }
      }
     },
     "localname": "GoodwillImpairedAccumulatedImpairmentLoss",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GrossProfit": {
     "auth_ref": [
      "r72"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 1.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_GuaranteesIndemnificationsAndWarrantiesPolicies": {
     "auth_ref": [
      "r103",
      "r233"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for guarantees, indemnifications and product warranties, and methodologies used in determining the amount of such liabilities.",
        "label": "Guarantees, Indemnifications and Warranties Policies [Policy Text Block]",
        "terseLabel": "Indemnification"
       }
      }
     },
     "localname": "GuaranteesIndemnificationsAndWarrantiesPolicies",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill": {
     "auth_ref": [
      "r93",
      "r209"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.",
        "label": "Impairment of Intangible Assets (Excluding Goodwill)",
        "terseLabel": "Impairment of intangible assets"
       }
      }
     },
     "localname": "ImpairmentOfIntangibleAssetsExcludingGoodwill",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic": {
     "auth_ref": [
      "r110"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofLossbeforeIncomeTaxesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments",
       "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": "United States"
       }
      }
     },
     "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofLossbeforeIncomeTaxesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest": {
     "auth_ref": [
      "r65",
      "r116",
      "r429",
      "r441",
      "r461"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 1.0,
       "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": "Income (loss) before income taxes",
        "totalLabel": "Income (loss) before income taxes"
       }
      }
     },
     "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign": {
     "auth_ref": [
      "r110"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofLossbeforeIncomeTaxesDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments",
       "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": "International"
       }
      }
     },
     "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofLossbeforeIncomeTaxesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments": {
     "auth_ref": [
      "r110"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofLossbeforeIncomeTaxesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.",
        "label": "Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest",
        "totalLabel": "Income (loss) before income taxes"
       }
      }
     },
     "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofLossbeforeIncomeTaxesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeStatementAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Income Statement [Abstract]",
        "terseLabel": "Income Statement [Abstract]"
       }
      }
     },
     "localname": "IncomeStatementAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncomeStatementLocationAxis": {
     "auth_ref": [
      "r215"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by location in the income statement.",
        "label": "Income Statement Location [Axis]",
        "terseLabel": "Income Statement Location [Axis]"
       }
      }
     },
     "localname": "IncomeStatementLocationAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncomeStatementLocationDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Location in the income statement.",
        "label": "Income Statement Location [Domain]",
        "terseLabel": "Income Statement Location [Domain]"
       }
      }
     },
     "localname": "IncomeStatementLocationDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_IncomeTaxAuthorityAxis": {
     "auth_ref": [
      "r341"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by tax jurisdiction.",
        "label": "Income Tax Authority [Axis]",
        "terseLabel": "Income Tax Authority [Axis]"
       }
      }
     },
     "localname": "IncomeTaxAuthorityAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "IncomeTaxAuthorityDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_IncomeTaxDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Income Tax Disclosure [Abstract]",
        "terseLabel": "Income Tax Disclosure [Abstract]"
       }
      }
     },
     "localname": "IncomeTaxDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncomeTaxDisclosureTextBlock": {
     "auth_ref": [
      "r366"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxes"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_IncomeTaxExpenseBenefit": {
     "auth_ref": [
      "r106",
      "r152",
      "r364"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 2.0,
       "parentTag": "us-gaap_NetIncomeLoss",
       "weight": -1.0
      },
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "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": "Provision for income taxes",
        "totalLabel": "Total provision for income taxes",
        "verboseLabel": "Provision for income taxes"
       }
      }
     },
     "localname": "IncomeTaxExpenseBenefit",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/IncomeTaxesScheduleofComponentsofProvisionforIncomeTaxesDetails",
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxPolicyTextBlock": {
     "auth_ref": [
      "r61",
      "r103",
      "r337",
      "r338",
      "r346",
      "r347",
      "r353",
      "r365",
      "r464"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance": {
     "auth_ref": [
      "r336",
      "r339",
      "r340"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "order": 8.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate": {
     "auth_ref": [
      "r105",
      "r339",
      "r340"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "order": 1.0,
       "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": "U.S. federal tax at statutory rate"
       }
      }
     },
     "localname": "IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther": {
     "auth_ref": [
      "r339",
      "r340"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "order": 3.0,
       "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 nondeductible expenses.",
        "label": "Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount",
        "terseLabel": "Non-deductible expense (benefit)"
       }
      }
     },
     "localname": "IncomeTaxReconciliationNondeductibleExpenseOther",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost": {
     "auth_ref": [
      "r339",
      "r340"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "order": 5.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationOtherAdjustments": {
     "auth_ref": [
      "r339"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "order": 7.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes": {
     "auth_ref": [
      "r105",
      "r339",
      "r340"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "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 income taxes"
       }
      }
     },
     "localname": "IncomeTaxReconciliationStateAndLocalIncomeTaxes",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxReconciliationTaxCreditsResearch": {
     "auth_ref": [
      "r339",
      "r340"
     ],
     "calculation": {
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails": {
       "order": 4.0,
       "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",
        "negatedTerseLabel": "Research and development credit"
       }
      }
     },
     "localname": "IncomeTaxReconciliationTaxCreditsResearch",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofEffectiveIncomeTaxAmountReconciliationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncomeTaxesPaidNet": {
     "auth_ref": [
      "r97"
     ],
     "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, net of any cash received during the current period as refunds for the overpayment of taxes.",
        "label": "Income Taxes Paid, Net",
        "terseLabel": "Cash paid for income taxes"
       }
      }
     },
     "localname": "IncomeTaxesPaidNet",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInAccountsPayableTrade": {
     "auth_ref": [
      "r92"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 13.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Change in recurring obligations of a business that arise from the acquisition of merchandise, materials, supplies and services used in the production and sale of goods and services.",
        "label": "Increase (Decrease) in Accounts Payable, Trade",
        "terseLabel": "Accounts payable"
       }
      }
     },
     "localname": "IncreaseDecreaseInAccountsPayableTrade",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInAccountsReceivable": {
     "auth_ref": [
      "r92"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 9.0,
       "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",
        "negatedTerseLabel": "Accounts receivable"
       }
      }
     },
     "localname": "IncreaseDecreaseInAccountsReceivable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInContractWithCustomerLiability": {
     "auth_ref": [
      "r92"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 16.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInOperatingCapitalAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Increase (Decrease) in Operating Capital [Abstract]",
        "terseLabel": "Changes in operating assets and liabilities:"
       }
      }
     },
     "localname": "IncreaseDecreaseInOperatingCapitalAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_IncreaseDecreaseInOtherNoncurrentAssets": {
     "auth_ref": [
      "r92"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 12.0,
       "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",
        "negatedTerseLabel": "Other assets"
       }
      }
     },
     "localname": "IncreaseDecreaseInOtherNoncurrentAssets",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 17.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of increase (decrease) in noncurrent operating liabilities classified as other.",
        "label": "Increase (Decrease) in Other Noncurrent Liabilities",
        "terseLabel": "Other liabilities"
       }
      }
     },
     "localname": "IncreaseDecreaseInOtherNoncurrentLiabilities",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets": {
     "auth_ref": [
      "r92"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 10.0,
       "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",
        "negatedTerseLabel": "Prepaid expenses and other current assets"
       }
      }
     },
     "localname": "IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInPropertyAndOtherTaxesPayable": {
     "auth_ref": [
      "r92"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 15.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The increase (decrease) during the period in the amount of cash payments due to taxing authorities for non-income-related taxes.",
        "label": "Increase (Decrease) in Property and Other Taxes Payable",
        "terseLabel": "Accrued federal fees and sales tax liability"
       }
      }
     },
     "localname": "IncreaseDecreaseInPropertyAndOtherTaxesPayable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_IncreaseDecreaseInStockholdersEquityRollForward": {
     "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": "Increase (Decrease) in Stockholders' Equity [Roll Forward]",
        "terseLabel": "Increase (Decrease) in Stockholders' Equity [Roll Forward]"
       }
      }
     },
     "localname": "IncreaseDecreaseInStockholdersEquityRollForward",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_IndemnificationGuaranteeMember": {
     "auth_ref": [
      "r230",
      "r234"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "An agreement (contract) that contingently requires the guarantor to make payments to the guaranteed party in compensation for that party's or parties' loss or injury attributable to specified events or actions, such as a patent infringement action against an entity that relied on certain representations as to ownership rights made by a software vendor.",
        "label": "Indemnification Agreement [Member]",
        "terseLabel": "Indemnification Agreement"
       }
      }
     },
     "localname": "IndemnificationGuaranteeMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_IntangibleAssetsNetExcludingGoodwill": {
     "auth_ref": [
      "r197",
      "r203"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 3.0,
       "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": "Intangible assets, net"
       }
      }
     },
     "localname": "IntangibleAssetsNetExcludingGoodwill",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InterestExpense": {
     "auth_ref": [
      "r63",
      "r150",
      "r395",
      "r398",
      "r444"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 1.0,
       "parentTag": "us-gaap_NonoperatingIncomeExpense",
       "weight": -1.0
      },
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails": {
       "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.",
        "label": "Interest Expense",
        "negatedTerseLabel": "Interest expense",
        "totalLabel": "Interest Expense"
       }
      }
     },
     "localname": "InterestExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_InterestExpenseDebt": {
     "auth_ref": [
      "r76",
      "r244"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_InterestExpense",
       "weight": 1.0
      }
     },
     "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",
        "terseLabel": "Contractual interest expense"
       }
      }
     },
     "localname": "InterestExpenseDebt",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails"
     ],
     "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 notes"
       }
      }
     },
     "localname": "InterestIncomeAndInterestExpenseDisclosureTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_InterestPaidNet": {
     "auth_ref": [
      "r87",
      "r89",
      "r97"
     ],
     "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": "Cash paid for interest"
       }
      }
     },
     "localname": "InterestPaidNet",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LeaseCostTableTextBlock": {
     "auth_ref": [
      "r416"
     ],
     "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 lease obligations"
       }
      }
     },
     "localname": "LeaseCostTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactTables",
      "http://www.five9.com/role/FinancialStatementComponentsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_LeaseholdImprovementsMember": {
     "auth_ref": [
      "r212"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Additions or improvements to assets held under a lease arrangement.",
        "label": "Leasehold Improvements [Member]",
        "terseLabel": "Leasehold Improvements"
       }
      }
     },
     "localname": "LeaseholdImprovementsMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LeasesAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Leases [Abstract]",
        "terseLabel": "Leases [Abstract]"
       }
      }
     },
     "localname": "LeasesAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_LesseeFinanceLeaseDescriptionAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Lessee, Finance Lease, Description [Abstract]",
        "terseLabel": "Finance lease cost:"
       }
      }
     },
     "localname": "LesseeFinanceLeaseDescriptionAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LesseeLeaseDescriptionTable": {
     "auth_ref": [
      "r409"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1": {
     "auth_ref": [
      "r408"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract",
        "terseLabel": "Operating lease not yet commenced, term of lease"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLeaseNotYetCommencedTermOfContract1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock": {
     "auth_ref": [
      "r417"
     ],
     "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 operating lease maturities"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityMaturityTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of lessee's undiscounted obligation for lease payments for operating lease.",
        "label": "Lessee, Operating Lease, Liability, Payments, Due",
        "totalLabel": "Total lease payments"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "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 payments for operating lease, due in fifth fiscal year following latest fiscal year.",
        "label": "Lessee, Operating Lease, Liability, Payments, Due Year Five",
        "terseLabel": "2024"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearFive",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "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 payments for operating lease, due in fourth fiscal year following latest fiscal year.",
        "label": "Lessee, Operating Lease, Liability, Payments, Due Year Four",
        "terseLabel": "2023"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearFour",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "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 payments for operating lease, due in third fiscal year following latest fiscal year.",
        "label": "Lessee, Operating Lease, Liability, Payments, Due Year Three",
        "terseLabel": "2022"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearThree",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "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 payments for operating lease, due in second fiscal year following latest fiscal year.",
        "label": "Lessee, Operating Lease, Liability, Payments, Due Year Two",
        "terseLabel": "2021"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearTwo",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails": {
       "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 payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.",
        "label": "Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year",
        "terseLabel": "2020"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount": {
     "auth_ref": [
      "r417"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "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 payments in excess of discounted obligation for lease payments for operating lease.",
        "label": "Lessee, Operating Lease, Liability, Undiscounted Excess Amount",
        "negatedTerseLabel": "Less: imputed interest"
       }
      }
     },
     "localname": "LesseeOperatingLeaseLiabilityUndiscountedExcessAmount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LesseeOperatingLeaseRenewalTerm": {
     "auth_ref": [
      "r407"
     ],
     "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 lease, extension term"
       }
      }
     },
     "localname": "LesseeOperatingLeaseRenewalTerm",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_LesseeOperatingLeaseTermOfContract": {
     "auth_ref": [
      "r407"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.",
        "label": "Lessee, Operating Lease, Term of Contract",
        "terseLabel": "Operating lease, term of contract"
       }
      }
     },
     "localname": "LesseeOperatingLeaseTermOfContract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_LesseeOperatingLeasesTextBlock": {
     "auth_ref": [
      "r419"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The entire disclosure for operating leases of lessee. Includes, but is not limited to, description of operating lease and maturity analysis of operating lease liability.",
        "label": "Lessee, Operating Leases [Text Block]",
        "terseLabel": "ASC 842 Adoption Impact"
       }
      }
     },
     "localname": "LesseeOperatingLeasesTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpact"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_Liabilities": {
     "auth_ref": [
      "r35"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 1.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LiabilitiesAndStockholdersEquity": {
     "auth_ref": [
      "r24",
      "r436",
      "r455"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "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 and stockholders\u2019 equity"
       }
      }
     },
     "localname": "LiabilitiesAndStockholdersEquity",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LiabilitiesAndStockholdersEquityAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Liabilities and Equity [Abstract]",
        "terseLabel": "LIABILITIES AND STOCKHOLDERS\u2019 EQUITY"
       }
      }
     },
     "localname": "LiabilitiesAndStockholdersEquityAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LiabilitiesCurrent": {
     "auth_ref": [
      "r37"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 1.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LineOfCreditFacilityLineItems": {
     "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": "Line of Credit Facility [Line Items]",
        "terseLabel": "Line of Credit Facility [Line Items]"
       }
      }
     },
     "localname": "LineOfCreditFacilityLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity": {
     "auth_ref": [
      "r34"
     ],
     "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": "Credit facility, maximum borrowing capacity"
       }
      }
     },
     "localname": "LineOfCreditFacilityMaximumBorrowingCapacity",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LineOfCreditFacilityTable": {
     "auth_ref": [
      "r34",
      "r108"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "A table or schedule providing information pertaining to short-term or long-term contractual arrangements with lenders, including letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to 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.",
        "label": "Line of Credit Facility [Table]",
        "terseLabel": "Line of Credit Facility [Table]"
       }
      }
     },
     "localname": "LineOfCreditFacilityTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "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": "Unused line of credit capacity fee"
       }
      }
     },
     "localname": "LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_LineOfCreditMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "A contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time, and under which borrowings outstanding may be either short-term or long-term, depending upon the particulars.",
        "label": "Line of Credit [Member]",
        "terseLabel": "Line of Credit"
       }
      }
     },
     "localname": "LineOfCreditMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LitigationSettlementAmountAwardedToOtherParty": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount awarded to other party in judgment or settlement of litigation.",
        "label": "Litigation Settlement, Amount Awarded to Other Party",
        "terseLabel": "Litigation settlement amount awarded to other party"
       }
      }
     },
     "localname": "LitigationSettlementAmountAwardedToOtherParty",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LitigationStatusAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by status of pending, threatened, or settled litigation.",
        "label": "Litigation Status [Axis]",
        "terseLabel": "Litigation Status [Axis]"
       }
      }
     },
     "localname": "LitigationStatusAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LitigationStatusDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Status of pending, threatened, or settled litigation.",
        "label": "Litigation Status [Domain]",
        "terseLabel": "Litigation Status [Domain]"
       }
      }
     },
     "localname": "LitigationStatusDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LongTermDebt": {
     "auth_ref": [
      "r13",
      "r241",
      "r435",
      "r453"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.",
        "label": "Long-term Debt",
        "totalLabel": "Total debt, net carrying value"
       }
      }
     },
     "localname": "LongTermDebt",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LongTermDebtFairValue": {
     "auth_ref": [],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.",
        "label": "Long-term Debt, Fair Value",
        "terseLabel": "Fair value of long-term debt"
       }
      }
     },
     "localname": "LongTermDebtFairValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive": {
     "auth_ref": [
      "r112",
      "r236"
     ],
     "calculation": {
      "http://www.five9.com/role/DebtScheduleofMaturitiesofDebtDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_DebtInstrumentCarryingAmount",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.",
        "label": "Long-term Debt, Maturities, Repayments of Principal in Year Five",
        "terseLabel": "2023"
       }
      }
     },
     "localname": "LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtScheduleofMaturitiesofDebtDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LongtermDebtTypeAxis": {
     "auth_ref": [
      "r40"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of long-term debt.",
        "label": "Long-term Debt, Type [Axis]",
        "terseLabel": "Long-term Debt, Type [Axis]"
       }
      }
     },
     "localname": "LongtermDebtTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlowsParenthetical",
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails",
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LongtermDebtTypeDomain": {
     "auth_ref": [
      "r40",
      "r237"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "LongtermDebtTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlowsParenthetical",
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails",
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails",
      "http://www.five9.com/role/DebtScheduleofEquityComponentofDebtDetails",
      "http://www.five9.com/role/DebtScheduleofInterestExpenseDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountofEquityComponentoftheNotesDetails",
      "http://www.five9.com/role/DebtScheduleofNetCarryingAmountoftheLiabilityComponentoftheNotesDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsNarrativeDetails",
      "http://www.five9.com/role/NetLossPerShareNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_LossContingenciesByNatureOfContingencyAxis": {
     "auth_ref": [
      "r220",
      "r221",
      "r222",
      "r224",
      "r225",
      "r226",
      "r228",
      "r231",
      "r232"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of existing condition, situation, or set of circumstances involving uncertainty as to possible loss to an enterprise that will ultimately be resolved when one or more future events occur or fail to occur.",
        "label": "Loss Contingency Nature [Axis]",
        "terseLabel": "Loss Contingency Nature [Axis]"
       }
      }
     },
     "localname": "LossContingenciesByNatureOfContingencyAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails",
      "http://www.five9.com/role/CommitmentsandContingenciesStateandLocalTaxesandSurchargesDetails",
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails",
      "http://www.five9.com/role/CommitmentsandContingenciesStateandLocalTaxesandSurchargesDetails",
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LossContingenciesTable": {
     "auth_ref": [
      "r220",
      "r221",
      "r222",
      "r224",
      "r225",
      "r226",
      "r228",
      "r231",
      "r232"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails",
      "http://www.five9.com/role/CommitmentsandContingenciesStateandLocalTaxesandSurchargesDetails",
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_LossContingencyDamagesPaidValue": {
     "auth_ref": [
      "r220",
      "r223",
      "r227"
     ],
     "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": "Settlement paid"
       }
      }
     },
     "localname": "LossContingencyDamagesPaidValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_LossContingencyNatureDomain": {
     "auth_ref": [
      "r220",
      "r221",
      "r222",
      "r224",
      "r225",
      "r226",
      "r228",
      "r231",
      "r232"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "An existing condition, situation, or set of circumstances involving uncertainty as to possible loss to an enterprise that will ultimately be resolved when one or more future events occur or fail to occur. Resolution of the uncertainty may confirm the incurrence of a loss or impairment of an asset or the incurrence of a liability.",
        "label": "Loss Contingency, Nature [Domain]",
        "terseLabel": "Loss Contingency, Nature [Domain]"
       }
      }
     },
     "localname": "LossContingencyNatureDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails",
      "http://www.five9.com/role/CommitmentsandContingenciesStateandLocalTaxesandSurchargesDetails",
      "http://www.five9.com/role/CommitmentsandContingenciesUniversalServicesFundLiabilityDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_MarketableSecuritiesPolicy": {
     "auth_ref": [
      "r445"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for investment classified as marketable security.",
        "label": "Marketable Securities, Policy [Policy Text Block]",
        "terseLabel": "Marketable Investments"
       }
      }
     },
     "localname": "MarketableSecuritiesPolicy",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_MoneyMarketFundsMember": {
     "auth_ref": [
      "r271"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Fund that invests in short-term money-market instruments, for example, but not limited to, commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and other highly liquid securities.",
        "label": "Money Market Funds [Member]",
        "terseLabel": "Money market funds"
       }
      }
     },
     "localname": "MoneyMarketFundsMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_MunicipalBondsMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Long-term debt securities issued by state, city or local governments or the agencies operated by state, city or local governments.",
        "label": "Municipal Bonds [Member]",
        "terseLabel": "Municipal bonds"
       }
      }
     },
     "localname": "MunicipalBondsMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_NetCashProvidedByUsedInFinancingActivities": {
     "auth_ref": [
      "r88"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 1.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]",
        "terseLabel": "Cash flows from financing activities:"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NetCashProvidedByUsedInInvestingActivities": {
     "auth_ref": [
      "r88"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 3.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract]",
        "terseLabel": "Cash flows from investing activities:"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NetCashProvidedByUsedInOperatingActivities": {
     "auth_ref": [
      "r88",
      "r91",
      "r94"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 2.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]",
        "terseLabel": "Cash flows from operating activities:"
       }
      }
     },
     "localname": "NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NetIncomeLoss": {
     "auth_ref": [
      "r55",
      "r58",
      "r66",
      "r94",
      "r129",
      "r442",
      "r459"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 18.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      },
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 1.0,
       "parentTag": "us-gaap_ComprehensiveIncomeNetOfTax",
       "weight": 1.0
      }
     },
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/NetLossPerShareBasicandDilutedNetLossPerShareDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems": {
     "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": "New Accounting Pronouncements or Change in Accounting Principle [Line Items]",
        "terseLabel": "New Accounting Pronouncements or Change in Accounting Principle [Line Items]"
       }
      }
     },
     "localname": "NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable": {
     "auth_ref": [
      "r115",
      "r117"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Summarization of the changes in an accounting principle or a new accounting pronouncement, including the line items affected by the change and the financial effects of the change on those particular line items.",
        "label": "New Accounting Pronouncements or Change in Accounting Principle [Table]",
        "terseLabel": "New Accounting Pronouncements or Change in Accounting Principle [Table]"
       }
      }
     },
     "localname": "NewAccountingPronouncementsOrChangeInAccountingPrincipleTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "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 Pronouncements"
       }
      }
     },
     "localname": "NewAccountingPronouncementsPolicyPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_NonUsMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Countries excluding the United States of America (US).",
        "label": "Non-US [Member]",
        "terseLabel": "International"
       }
      }
     },
     "localname": "NonUsMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_NoncashInvestingAndFinancingItemsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Noncash Investing and Financing Items [Abstract]",
        "terseLabel": "Non-cash investing and financing activities:"
       }
      }
     },
     "localname": "NoncashInvestingAndFinancingItemsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1": {
     "auth_ref": [
      "r98",
      "r99",
      "r100"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The amount of fixed assets that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but 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": "Noncash or Part Noncash Acquisition, Fixed Assets Acquired",
        "terseLabel": "Equipment obtained under finance lease"
       }
      }
     },
     "localname": "NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NonoperatingIncomeExpense": {
     "auth_ref": [
      "r75"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "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)",
        "totalLabel": "Total other income (expense), net"
       }
      }
     },
     "localname": "NonoperatingIncomeExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_NonoperatingIncomeExpenseAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Nonoperating Income (Expense) [Abstract]",
        "terseLabel": "Other income (expense), net:"
       }
      }
     },
     "localname": "NonoperatingIncomeExpenseAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OperatingExpenses": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 2.0,
       "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OperatingIncomeLoss": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 1.0,
       "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": "Income (loss) from operations"
       }
      }
     },
     "localname": "OperatingIncomeLoss",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseCost": {
     "auth_ref": [
      "r411",
      "r418"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Lessee, Operating Lease, Liability, Payment, Due [Abstract]",
        "terseLabel": "Operating Leases"
       }
      }
     },
     "localname": "OperatingLeaseLiabilitiesPaymentsDueAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OperatingLeaseLiability": {
     "auth_ref": [
      "r403"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      },
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails_1": {
       "order": 1.0,
       "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Present value of lessee's discounted obligation for lease payments from operating lease.",
        "label": "Operating Lease, Liability",
        "terseLabel": "Operating lease liability",
        "totalLabel": "Total operating lease liabilities",
        "verboseLabel": "Total"
       }
      }
     },
     "localname": "OperatingLeaseLiability",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseMaturitiesDetails",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseLiabilityCurrent": {
     "auth_ref": [
      "r403"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_OperatingLeaseLiability",
       "weight": 1.0
      },
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 5.0,
       "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": "Operating lease liabilities"
       }
      }
     },
     "localname": "OperatingLeaseLiabilityCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseLiabilityNoncurrent": {
     "auth_ref": [
      "r403"
     ],
     "calculation": {
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_OperatingLeaseLiability",
       "weight": 1.0
      },
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 5.0,
       "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 \u2014 less current portion"
       }
      }
     },
     "localname": "OperatingLeaseLiabilityNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeasePayments": {
     "auth_ref": [
      "r406",
      "r412"
     ],
     "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",
        "negatedTerseLabel": "Operating cash used in operating leases"
       }
      }
     },
     "localname": "OperatingLeasePayments",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseRightOfUseAsset": {
     "auth_ref": [
      "r402"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 7.0,
       "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 Asset"
       }
      }
     },
     "localname": "OperatingLeaseRightOfUseAsset",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetDisclosuresDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent": {
     "auth_ref": [
      "r415",
      "r418"
     ],
     "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, Operating leases"
       }
      }
     },
     "localname": "OperatingLeaseWeightedAverageDiscountRatePercent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactWeightedAverageRemainingTermsandDiscountRatesDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1": {
     "auth_ref": [
      "r414",
      "r418"
     ],
     "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, Operating leases"
       }
      }
     },
     "localname": "OperatingLeaseWeightedAverageRemainingLeaseTerm1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactWeightedAverageRemainingTermsandDiscountRatesDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_OperatingLossCarryforwards": {
     "auth_ref": [
      "r354"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.",
        "label": "Operating Loss Carryforwards",
        "terseLabel": "Net operating loss carryforwards"
       }
      }
     },
     "localname": "OperatingLossCarryforwards",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OperatingLossCarryforwardsLineItems": {
     "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": "Operating Loss Carryforwards [Line Items]",
        "terseLabel": "Operating Loss Carryforwards [Line Items]"
       }
      }
     },
     "localname": "OperatingLossCarryforwardsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OperatingLossCarryforwardsTable": {
     "auth_ref": [
      "r355"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Schedule reflecting pertinent information, such as tax authority, amounts, and expiration dates, of net operating loss carryforwards, including an assessment of the likelihood of utilization.",
        "label": "Operating Loss Carryforwards [Table]",
        "terseLabel": "Operating Loss Carryforwards [Table]"
       }
      }
     },
     "localname": "OperatingLossCarryforwardsTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock": {
     "auth_ref": [
      "r0",
      "r113",
      "r149",
      "r382"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The entire disclosure for the organization, consolidation and basis of presentation of financial statements disclosure, and significant accounting policies of the reporting entity. May be provided in more than one note to the financial statements, as long as users are provided with an understanding of (1) the significant judgments and assumptions made by an enterprise in determining whether it must consolidate a VIE and/or disclose information about its involvement with a VIE, (2) the nature of restrictions on a consolidated VIE's assets reported by an enterprise in its statement of financial position, including the carrying amounts of such assets, (3) the nature of, and changes in, the risks associated with an enterprise's involvement with the VIE, and (4) how an enterprise's involvement with the VIE affects the enterprise's financial position, financial performance, and cash flows.  Describes procedure if disclosures are provided in more than one note to the financial statements.",
        "label": "Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block]",
        "terseLabel": "Description of Business and Summary of Significant Accounting Policies"
       }
      }
     },
     "localname": "OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_OtherAssetsCurrent": {
     "auth_ref": [
      "r47"
     ],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_PrepaidExpenseAndOtherAssetsCurrent",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of current assets classified as other.",
        "label": "Other Assets, Current",
        "terseLabel": "Other current assets"
       }
      }
     },
     "localname": "OtherAssetsCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherAssetsNoncurrent": {
     "auth_ref": [
      "r32"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 5.0,
       "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 assets"
       }
      }
     },
     "localname": "OtherAssetsNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Other Comprehensive Income (Loss), Net of Tax [Abstract]",
        "terseLabel": "Comprehensive Loss:"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent": {
     "auth_ref": [
      "r56",
      "r59",
      "r377",
      "r378",
      "r379"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 2.0,
       "parentTag": "us-gaap_ComprehensiveIncomeNetOfTax",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount after tax of other comprehensive income (loss) attributable to parent entity.",
        "label": "Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent",
        "terseLabel": "Other comprehensive income (loss)"
       }
      }
     },
     "localname": "OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "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": "Schedule of accrued and other current liabilities"
       }
      }
     },
     "localname": "OtherCurrentLiabilitiesTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_OtherLiabilitiesNoncurrent": {
     "auth_ref": [
      "r41"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "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"
       }
      }
     },
     "localname": "OtherLiabilitiesNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherNoncashIncomeExpense": {
     "auth_ref": [
      "r94"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 8.0,
       "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": "Others"
       }
      }
     },
     "localname": "OtherNoncashIncomeExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_OtherNonoperatingIncomeExpense": {
     "auth_ref": [
      "r77"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 2.0,
       "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)",
        "terseLabel": "Interest income and other"
       }
      }
     },
     "localname": "OtherNonoperatingIncomeExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsForLegalSettlements": {
     "auth_ref": [
      "r90"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The amount of cash paid for the settlement of litigation or for other legal issues during the period.",
        "label": "Payments for Legal Settlements",
        "terseLabel": "Legal fees"
       }
      }
     },
     "localname": "PaymentsForLegalSettlements",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsOfDebtIssuanceCosts": {
     "auth_ref": [
      "r86"
     ],
     "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",
        "terseLabel": "Payment on debt issuance cost"
       }
      }
     },
     "localname": "PaymentsOfDebtIssuanceCosts",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlowsParenthetical",
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation": {
     "auth_ref": [
      "r84"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 5.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.",
        "label": "Payment, Tax Withholding, Share-based Payment Arrangement",
        "negatedTerseLabel": "Payments of employee taxes related to vested common stock"
       }
      }
     },
     "localname": "PaymentsRelatedToTaxWithholdingForShareBasedCompensation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt": {
     "auth_ref": [
      "r78",
      "r80",
      "r164"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 1.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of cash outflow to acquire investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).",
        "label": "Payments to Acquire Debt Securities, Available-for-sale",
        "negatedTerseLabel": "Purchases of marketable investments"
       }
      }
     },
     "localname": "PaymentsToAcquireAvailableForSaleSecuritiesDebt",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PaymentsToAcquirePropertyPlantAndEquipment": {
     "auth_ref": [
      "r81"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 3.0,
       "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",
        "negatedTerseLabel": "Purchases of property and equipment"
       }
      }
     },
     "localname": "PaymentsToAcquirePropertyPlantAndEquipment",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock": {
     "auth_ref": [
      "r276"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The entire disclosure for pension and other postretirement benefits.",
        "label": "Pension and Other Postretirement Benefits Disclosure [Text Block]",
        "terseLabel": "Retirement Plans"
       }
      }
     },
     "localname": "PensionAndOtherPostretirementBenefitsDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RetirementPlans"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_PlanNameAxis": {
     "auth_ref": [
      "r281",
      "r313"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by plan name for share-based payment arrangement.",
        "label": "Plan Name [Axis]",
        "terseLabel": "Plan Name [Axis]"
       }
      }
     },
     "localname": "PlanNameAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_PlanNameDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Plan name for share-based payment arrangement.",
        "label": "Plan Name [Domain]",
        "terseLabel": "Plan Name [Domain]"
       }
      }
     },
     "localname": "PlanNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_PostemploymentBenefitsPeriodExpense": {
     "auth_ref": [],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Period expense related to postemployment benefits.",
        "label": "Postemployment Benefits, Period Expense",
        "terseLabel": "Retirement expense"
       }
      }
     },
     "localname": "PostemploymentBenefitsPeriodExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RetirementPlansDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PreferredStockParOrStatedValuePerShare": {
     "auth_ref": [
      "r17"
     ],
     "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 (in USD per share)"
       }
      }
     },
     "localname": "PreferredStockParOrStatedValuePerShare",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_PreferredStockSharesAuthorized": {
     "auth_ref": [
      "r17"
     ],
     "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",
        "verboseLabel": "Preferred stock, shares authorized (in shares)"
       }
      }
     },
     "localname": "PreferredStockSharesAuthorized",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_PreferredStockSharesIssued": {
     "auth_ref": [
      "r17"
     ],
     "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 (in shares)"
       }
      }
     },
     "localname": "PreferredStockSharesIssued",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_PreferredStockSharesOutstanding": {
     "auth_ref": [
      "r17"
     ],
     "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",
        "terseLabel": "Preferred stock, shares outstanding (in shares)"
       }
      }
     },
     "localname": "PreferredStockSharesOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheetsParenthetical",
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_PreferredStockValueOutstanding": {
     "auth_ref": [
      "r17"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 1.0,
       "parentTag": "us-gaap_StockholdersEquity",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Value of all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by shareholders, which is net of related treasury stock. May be all or a portion of the number of preferred shares authorized. These shares represent the ownership interest of the preferred shareholders.",
        "label": "Preferred Stock, Value, Outstanding",
        "terseLabel": "Preferred stock, $0.001 par value; 5,000 shares authorized, no shares issued and outstanding as of December 31, 2019 and 2018"
       }
      }
     },
     "localname": "PreferredStockValueOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PrepaidExpenseAndOtherAssetsCurrent": {
     "auth_ref": [
      "r4",
      "r26",
      "r27"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 4.0,
       "parentTag": "us-gaap_AssetsCurrent",
       "weight": 1.0
      },
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "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",
        "totalLabel": "Prepaid expenses and other current assets"
       }
      }
     },
     "localname": "PrepaidExpenseAndOtherAssetsCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PrepaidExpenseCurrent": {
     "auth_ref": [
      "r3",
      "r5",
      "r189"
     ],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_PrepaidExpenseAndOtherAssetsCurrent",
       "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 within a future period of one year or the normal operating cycle, if longer.",
        "label": "Prepaid Expense, Current",
        "terseLabel": "Prepaid expenses"
       }
      }
     },
     "localname": "PrepaidExpenseCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPrepaidExpensesandOtherCurrentAssetsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PrimeRateMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Interest rate charged by financial institutions to their most creditworthy borrowers.",
        "label": "Prime Rate [Member]",
        "terseLabel": "Prime Rate"
       }
      }
     },
     "localname": "PrimeRateMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ProceedsFromConvertibleDebt": {
     "auth_ref": [
      "r83"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 1.0,
       "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 issuance costs paid $8,039"
       }
      }
     },
     "localname": "ProceedsFromConvertibleDebt",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromIssuanceOfDebt": {
     "auth_ref": [
      "r83"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.",
        "label": "Proceeds from Issuance of Debt",
        "terseLabel": "Proceeds from issuance of debt"
       }
      }
     },
     "localname": "ProceedsFromIssuanceOfDebt",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtConvertibleSeniorNotesandCappedCallDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions": {
     "auth_ref": [
      "r82",
      "r314"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 4.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of cash inflow from issuance of shares under share-based payment arrangement. Includes, but is not limited to, option exercised.",
        "label": "Proceeds, Issuance of Shares, Share-based Payment Arrangement, Including Option Exercised",
        "terseLabel": "Proceeds from sale of common stock under ESPP"
       }
      }
     },
     "localname": "ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities": {
     "auth_ref": [
      "r78",
      "r79",
      "r164"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 2.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of cash inflow from sale, maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).",
        "label": "Proceeds from Sale and Maturity of Debt Securities, Available-for-sale",
        "terseLabel": "Proceeds from maturities of marketable investments"
       }
      }
     },
     "localname": "ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromSaleOfNotesReceivable": {
     "auth_ref": [
      "r79"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 5.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities",
       "weight": 1.0
      }
     },
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The cash inflow associated with the sale of a borrowing supported by a written promise to pay an obligation.",
        "label": "Proceeds from Sale of Notes Receivable",
        "terseLabel": "Proceeds from sale of convertible note held for investment"
       }
      }
     },
     "localname": "ProceedsFromSaleOfNotesReceivable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ProceedsFromStockOptionsExercised": {
     "auth_ref": [
      "r82",
      "r314"
     ],
     "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",
        "verboseLabel": "Cash received from options exercised"
       }
      }
     },
     "localname": "ProceedsFromStockOptionsExercised",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentByTypeAxis": {
     "auth_ref": [
      "r31",
      "r214"
     ],
     "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": "Property, Plant and Equipment, Type [Axis]",
        "terseLabel": "Property, Plant and Equipment, Type [Axis]"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentByTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentGross": {
     "auth_ref": [
      "r30",
      "r212"
     ],
     "calculation": {
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails": {
       "order": 1.0,
       "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",
        "terseLabel": "Property and equipment"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentGross",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentNet": {
     "auth_ref": [
      "r9",
      "r10",
      "r214",
      "r456"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 2.0,
       "parentTag": "us-gaap_Assets",
       "weight": 1.0
      },
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails": {
       "order": null,
       "parentTag": null,
       "root": true,
       "weight": null
      }
     },
     "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",
        "verboseLabel": "Property and equipment, net"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentNet",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails",
      "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentPolicyTextBlock": {
     "auth_ref": [
      "r29",
      "r103",
      "r214"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, basis of assets, depreciation and depletion methods used, including composite deprecation, estimated useful lives, capitalization policy, accounting treatment for costs incurred for repairs and maintenance, capitalized interest and the method it is calculated, disposals and impairments.",
        "label": "Property, Plant and Equipment, Policy [Policy Text Block]",
        "terseLabel": "Property and Equipment, Net"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentTextBlock": {
     "auth_ref": [
      "r9",
      "r214"
     ],
     "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": "Schedule of property and equipment",
        "verboseLabel": "Schedule of useful lives of property and equipment"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesTables",
      "http://www.five9.com/role/FinancialStatementComponentsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_PropertyPlantAndEquipmentTypeDomain": {
     "auth_ref": [
      "r9",
      "r212"
     ],
     "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": "Property, Plant and Equipment, Type [Domain]",
        "terseLabel": "Property, Plant and Equipment, Type [Domain]"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "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": "Useful life, in years"
       }
      }
     },
     "localname": "PropertyPlantAndEquipmentUsefulLife",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_ProvisionForDoubtfulAccounts": {
     "auth_ref": [
      "r69",
      "r176"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 3.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities",
       "weight": 1.0
      }
     },
     "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)",
        "terseLabel": "Provision for doubtful accounts",
        "verboseLabel": "Add: bad debt expense"
       }
      }
     },
     "localname": "ProvisionForDoubtfulAccounts",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesAllowanceforDoubtfulAccountsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligation": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails": {
       "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 future minimum payment"
       }
      }
     },
     "localname": "PurchaseObligation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInFourthYear": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails": {
       "order": 4.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Minimum amount of purchase arrangement maturing in the fourth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.",
        "label": "Purchase Obligation, Due in Fourth Year",
        "terseLabel": "2023"
       }
      }
     },
     "localname": "PurchaseObligationDueInFourthYear",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInNextTwelveMonths": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails": {
       "order": 1.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.",
        "label": "Purchase Obligation, Due in Next Twelve Months",
        "terseLabel": "2020"
       }
      }
     },
     "localname": "PurchaseObligationDueInNextTwelveMonths",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInSecondYear": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails": {
       "order": 2.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Minimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.",
        "label": "Purchase Obligation, Due in Second Year",
        "terseLabel": "2021"
       }
      }
     },
     "localname": "PurchaseObligationDueInSecondYear",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_PurchaseObligationDueInThirdYear": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails": {
       "order": 3.0,
       "parentTag": "us-gaap_PurchaseObligation",
       "weight": 1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Minimum amount of purchase arrangement maturing in the third fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.",
        "label": "Purchase Obligation, Due in Third Year",
        "terseLabel": "2022"
       }
      }
     },
     "localname": "PurchaseObligationDueInThirdYear",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_QuarterlyFinancialInformationDisclosureAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Quarterly Financial Information Disclosure [Abstract]",
        "terseLabel": "Quarterly Financial Information Disclosure [Abstract]"
       }
      }
     },
     "localname": "QuarterlyFinancialInformationDisclosureAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_QuarterlyFinancialInformationTextBlock": {
     "auth_ref": [
      "r140"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The entire disclosure for quarterly financial data. Includes, but is not limited to, tabular presentation of financial information for fiscal quarters, effect of year-end adjustments, and an explanation of matters or transactions that affect comparability of the information.",
        "label": "Quarterly Financial Information [Text Block]",
        "terseLabel": "Selected Quarterly Financial Data (Unaudited)"
       }
      }
     },
     "localname": "QuarterlyFinancialInformationTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnaudited"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ReceivablesBillingStatusDomain": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amounts due from customers (or dealers) within the next year (or operating cycle, if longer) for goods or services that have been delivered or used, but not yet paid.",
        "label": "Receivables Billing Status [Domain]",
        "terseLabel": "Receivables Billing Status [Domain]"
       }
      }
     },
     "localname": "ReceivablesBillingStatusDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ReceivablesTradeAndOtherAccountsReceivableAllowanceForDoubtfulAccountsPolicy": {
     "auth_ref": [
      "r25",
      "r103",
      "r161"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for determining the allowance for doubtful accounts for trade and other accounts receivable balances, and when impairments, charge-offs or recoveries are recognized.",
        "label": "Receivables, Trade and Other Accounts Receivable, Allowance for Doubtful Accounts, Policy [Policy Text Block]",
        "terseLabel": "Allowance for Doubtful Accounts"
       }
      }
     },
     "localname": "ReceivablesTradeAndOtherAccountsReceivableAllowanceForDoubtfulAccountsPolicy",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward": {
     "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": "Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]",
        "terseLabel": "Reconciliation of Unrecognized Tax Benefits"
       }
      }
     },
     "localname": "ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofUnrecognizedTaxBenefitsRollforwardDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_RepaymentsOfLinesOfCredit": {
     "auth_ref": [
      "r85",
      "r109"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 6.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.",
        "label": "Repayments of Lines of Credit",
        "negatedTerseLabel": "Repayments on revolving line of credit"
       }
      }
     },
     "localname": "RepaymentsOfLinesOfCredit",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RepaymentsOfLongTermCapitalLeaseObligations": {
     "auth_ref": [
      "r85"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 8.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The cash outflow for the obligation for a lease meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer).",
        "label": "Repayments of Long-term Capital Lease Obligations",
        "negatedTerseLabel": "Payments of finance leases"
       }
      }
     },
     "localname": "RepaymentsOfLongTermCapitalLeaseObligations",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RepaymentsOfSecuredDebt": {
     "auth_ref": [
      "r85"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 7.0,
       "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities",
       "weight": -1.0
      }
     },
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.",
        "label": "Repayments of Secured Debt",
        "negatedTerseLabel": "Repayments of notes payable"
       }
      }
     },
     "localname": "RepaymentsOfSecuredDebt",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ResearchAndDevelopmentExpense": {
     "auth_ref": [
      "r332",
      "r466"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 1.0,
       "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"
       }
      }
     },
     "localname": "ResearchAndDevelopmentExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "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"
       }
      }
     },
     "localname": "ResearchAndDevelopmentExpenseMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ResearchAndDevelopmentExpensePolicy": {
     "auth_ref": [
      "r103",
      "r332"
     ],
     "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"
       }
      }
     },
     "localname": "ResearchAndDevelopmentExpensePolicy",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ResearchMember": {
     "auth_ref": [
      "r355"
     ],
     "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"
       }
      }
     },
     "localname": "ResearchMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Type of cash and cash equivalent. Cash is 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.",
        "label": "Cash and Cash Equivalents [Domain]",
        "terseLabel": "Cash and Cash Equivalents [Domain]"
       }
      }
     },
     "localname": "RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "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 outstanding"
       }
      }
     },
     "localname": "RestrictedStockUnitsRSUMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails",
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails",
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_RetainedEarningsAccumulatedDeficit": {
     "auth_ref": [
      "r21",
      "r257",
      "r454"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 5.0,
       "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"
       }
      }
     },
     "localname": "RetainedEarningsAccumulatedDeficit",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RetainedEarningsMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The cumulative amount of the reporting entity's undistributed earnings or deficit.",
        "label": "Retained Earnings [Member]",
        "terseLabel": "Accumulated Deficit"
       }
      }
     },
     "localname": "RetainedEarningsMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_RevenueFromContractWithCustomerAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Revenue from Contract with Customer [Abstract]",
        "terseLabel": "Revenue from Contract with Customer [Abstract]"
       }
      }
     },
     "localname": "RevenueFromContractWithCustomerAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax": {
     "auth_ref": [
      "r264",
      "r265"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 1.0,
       "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": "Revenue"
       }
      }
     },
     "localname": "RevenueFromContractWithCustomerExcludingAssessedTax",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails",
      "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RevenueFromContractWithCustomerPolicyTextBlock": {
     "auth_ref": [
      "r104",
      "r270"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_RevenueFromContractWithCustomerTextBlock": {
     "auth_ref": [
      "r270"
     ],
     "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"
       }
      }
     },
     "localname": "RevenueFromContractWithCustomerTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Revenue"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems": {
     "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": "Revenue, Initial Application Period Cumulative Effect Transition [Line Items]",
        "terseLabel": "Revenue, Initial Application Period Cumulative Effect Transition [Line Items]"
       }
      }
     },
     "localname": "RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RevenueNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of information when using transition method for cumulative effect in initial period of application for revenue from contract with customer.",
        "label": "Revenue, Initial Application Period Cumulative Effect Transition [Table]",
        "terseLabel": "Revenue, Initial Application Period Cumulative Effect Transition [Table]"
       }
      }
     },
     "localname": "RevenueInitialApplicationPeriodCumulativeEffectTransitionTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RevenueNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_RevenueRemainingPerformanceObligation": {
     "auth_ref": [
      "r263"
     ],
     "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": "Remaining performance obligation"
       }
      }
     },
     "localname": "RevenueRemainingPerformanceObligation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/RevenueNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "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"
       }
      }
     },
     "localname": "RevenuesFromExternalCustomersAndLongLivedAssetsLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_RevolvingCreditFacilityMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Arrangement in which loan proceeds can continuously be obtained following repayments, but the total amount borrowed cannot exceed a specified maximum amount.",
        "label": "Revolving Credit Facility [Member]",
        "terseLabel": "Revolving Credit Facility"
       }
      }
     },
     "localname": "RevolvingCreditFacilityMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability": {
     "auth_ref": [
      "r413",
      "r418"
     ],
     "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": "Right of use assets obtained in exchange for finance leases"
       }
      }
     },
     "localname": "RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability": {
     "auth_ref": [
      "r413",
      "r418"
     ],
     "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": "Right-of-use assets obtained in exchange for operating leases"
       }
      }
     },
     "localname": "RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactLeaseCostandSupplementalCashFlowDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SalesAndExciseTaxPayableCurrent": {
     "auth_ref": [
      "r7",
      "r33"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 7.0,
       "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 through that date and payable for statutory sales and use taxes, including value added tax. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).",
        "label": "Sales and Excise Tax Payable, Current",
        "terseLabel": "Sales tax liabilities",
        "verboseLabel": "Sales tax liability - current"
       }
      }
     },
     "localname": "SalesAndExciseTaxPayableCurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesStateandLocalTaxesandSurchargesDetails",
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SalesAndExciseTaxPayableCurrentAndNoncurrent": {
     "auth_ref": [
      "r438",
      "r458"
     ],
     "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": "Sales tax liability"
       }
      }
     },
     "localname": "SalesAndExciseTaxPayableCurrentAndNoncurrent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesStateandLocalTaxesandSurchargesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SalesCommissionsAndFees": {
     "auth_ref": [
      "r74"
     ],
     "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": "Commission expense"
       }
      }
     },
     "localname": "SalesCommissionsAndFees",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesCommissionsDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable": {
     "auth_ref": [
      "r46"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock": {
     "auth_ref": [
      "r46"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of the various 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 Text Block]",
        "terseLabel": "Schedule of accounts receivable"
       }
      }
     },
     "localname": "ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable": {
     "auth_ref": [
      "r199"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of the major classes of acquired finite-lived intangible assets showing the amount, any significant residual value, weighted average amortization period, and other characteristics. A major class is composed of intangible assets that can be grouped together because they are similar, either by nature or by their use in the operations of the company.",
        "label": "Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table]",
        "terseLabel": "Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table]"
       }
      }
     },
     "localname": "ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsScheduleofIntangibleAssetsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock": {
     "auth_ref": [
      "r199"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of the characteristics, including initial carrying value, residual amount, weighted average useful life, of finite-lived intangible assets acquired during the period by major class. A major class is composed of intangible assets that can be grouped together because they are similar, either by nature or by their use in the operations of the company.",
        "label": "Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block]",
        "terseLabel": "Schedule of intangible assets"
       }
      }
     },
     "localname": "ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable": {
     "auth_ref": [
      "r128"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock": {
     "auth_ref": [
      "r128"
     ],
     "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 securities excluded from calculation of diluted net loss per share"
       }
      }
     },
     "localname": "ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems": {
     "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 Securities, Available-for-sale [Line Items]",
        "terseLabel": "Debt Securities, Available-for-sale [Line Items]"
       }
      }
     },
     "localname": "ScheduleOfAvailableForSaleSecuritiesLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfCashAndCashEquivalentsTable": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Schedule of cash and cash equivalent balances. This table excludes restricted cash balances.",
        "label": "Schedule of Cash and Cash Equivalents [Table]",
        "terseLabel": "Schedule of Cash and Cash Equivalents [Table]"
       }
      }
     },
     "localname": "ScheduleOfCashAndCashEquivalentsTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofCashandCashEquivalentsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfCashAndCashEquivalentsTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of the components of cash and cash equivalents.",
        "label": "Schedule of Cash and Cash Equivalents [Table Text Block]",
        "terseLabel": "Schedule of cash and cash equivalents"
       }
      }
     },
     "localname": "ScheduleOfCashAndCashEquivalentsTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock": {
     "auth_ref": [
      "r359"
     ],
     "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 components of provision for income taxes"
       }
      }
     },
     "localname": "ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfCreditLossesForFinancingReceivablesCurrentTableTextBlock": {
     "auth_ref": [
      "r159",
      "r178"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of allowance for credit loss of financing receivable, classified as current.",
        "label": "Financing Receivable, Current, Allowance for Credit Loss [Table Text Block]",
        "terseLabel": "Schedule of allowance for doubtful accounts"
       }
      }
     },
     "localname": "ScheduleOfCreditLossesForFinancingReceivablesCurrentTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock": {
     "auth_ref": [
      "r352"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock": {
     "auth_ref": [
      "r129"
     ],
     "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": "Schedule of basic and diluted net loss per share"
       }
      }
     },
     "localname": "ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock": {
     "auth_ref": [
      "r339"
     ],
     "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": "Schedule of effective income tax reconciliation"
       }
      }
     },
     "localname": "ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable": {
     "auth_ref": [
      "r279",
      "r310",
      "r326"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock": {
     "auth_ref": [
      "r279",
      "r310",
      "r326"
     ],
     "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": "Schedule of stock-based compensation expense"
       }
      }
     },
     "localname": "ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable": {
     "auth_ref": [
      "r199",
      "r204"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Schedule of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.",
        "label": "Schedule of Finite-Lived Intangible Assets [Table]",
        "terseLabel": "Schedule of Finite-Lived Intangible Assets [Table]"
       }
      }
     },
     "localname": "ScheduleOfFiniteLivedIntangibleAssetsTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesGoodwillandIntangibleAssetsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock": {
     "auth_ref": [
      "r110"
     ],
     "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": "Schedule of components of loss before income taxes"
       }
      }
     },
     "localname": "ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock": {
     "auth_ref": [
      "r236"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of the combined aggregate amount of maturities and sinking fund requirements for all long-term borrowings for each of the five years following the date of the latest balance sheet date presented.",
        "label": "Schedule of Maturities of Long-term Debt [Table Text Block]",
        "terseLabel": "Schedule of maturities of debt"
       }
      }
     },
     "localname": "ScheduleOfMaturitiesOfLongTermDebtTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DebtTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock": {
     "auth_ref": [
      "r115",
      "r117",
      "r133",
      "r134",
      "r139"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.",
        "label": "Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]",
        "terseLabel": "Schedule of impacts from new accounting pronouncements"
       }
      }
     },
     "localname": "ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfPropertyPlantAndEquipmentTable": {
     "auth_ref": [
      "r31",
      "r214"
     ],
     "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": "Property, Plant and Equipment [Table]"
       }
      }
     },
     "localname": "ScheduleOfPropertyPlantAndEquipmentTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock": {
     "auth_ref": [
      "r136"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of quarterly financial data. Includes, but is not limited to, financial information for fiscal quarters, cumulative effect of a change in accounting principle and earnings per share data.",
        "label": "Quarterly Financial Information [Table Text Block]",
        "terseLabel": "Schedule of Quarterly Financial Information"
       }
      }
     },
     "localname": "ScheduleOfQuarterlyFinancialInformationTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock": {
     "auth_ref": [
      "r71",
      "r154"
     ],
     "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": "Schedule of revenues and property and equipment by geographic region"
       }
      }
     },
     "localname": "ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GeographicalInformationTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable": {
     "auth_ref": [
      "r62",
      "r64",
      "r154"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GeographicalInformationScheduleofRevenueandPropertyandEquipmentbyGeographicRegionDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable": {
     "auth_ref": [
      "r281",
      "r313"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails",
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock": {
     "auth_ref": [
      "r288"
     ],
     "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": "Schedule of RSU activities"
       }
      }
     },
     "localname": "ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock": {
     "auth_ref": [
      "r288",
      "r299",
      "r302"
     ],
     "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": "Schedule of stock option activities"
       }
      }
     },
     "localname": "ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfShareBasedPaymentAwardEmployeeStockPurchasePlanValuationAssumptionsTableTextBlock": {
     "auth_ref": [
      "r304"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of the significant assumptions used during the year to estimate the fair value of employee stock purchase plans, including, but not limited to: (a) expected term, (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, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]",
        "terseLabel": "Schedule of valuation assumptions for stock option purchase plan"
       }
      }
     },
     "localname": "ScheduleOfShareBasedPaymentAwardEmployeeStockPurchasePlanValuationAssumptionsTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock": {
     "auth_ref": [
      "r304"
     ],
     "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": "Schedule of valuation assumptions, stock option"
       }
      }
     },
     "localname": "ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfStockByClassTable": {
     "auth_ref": [
      "r43",
      "r107",
      "r246",
      "r247",
      "r248",
      "r250",
      "r251",
      "r252",
      "r254",
      "r255",
      "r256",
      "r257"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails",
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails",
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ScheduleOfUnrecognizedCompensationCostNonvestedAwardsTableTextBlock": {
     "auth_ref": [
      "r312"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of cost not yet recognized and weighted-average period over which cost is expected to be recognized for nonvested award under share-based payment arrangement.",
        "label": "Share-based Payment Arrangement, Nonvested Award, Cost [Table Text Block]",
        "terseLabel": "Schedule of unrecognized compensation expense"
       }
      }
     },
     "localname": "ScheduleOfUnrecognizedCompensationCostNonvestedAwardsTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock": {
     "auth_ref": [
      "r345",
      "r360"
     ],
     "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": "Schedule of unrecognized tax benefits rollforward"
       }
      }
     },
     "localname": "ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock": {
     "auth_ref": [
      "r204"
     ],
     "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": "Schedule of expected future amortization expense of intangible assets"
       }
      }
     },
     "localname": "ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GoodwillandIntangibleAssetsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SegmentReportingAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Segment Reporting [Abstract]",
        "terseLabel": "Segment Reporting [Abstract]"
       }
      }
     },
     "localname": "SegmentReportingAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_SegmentReportingDisclosureTextBlock": {
     "auth_ref": [
      "r155"
     ],
     "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": "Geographical Information"
       }
      }
     },
     "localname": "SegmentReportingDisclosureTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/GeographicalInformation"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SegmentReportingPolicyPolicyTextBlock": {
     "auth_ref": [
      "r103"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Disclosure of accounting policy for segment reporting.",
        "label": "Segment Reporting, Policy [Policy Text Block]",
        "terseLabel": "Segment Information"
       }
      }
     },
     "localname": "SegmentReportingPolicyPolicyTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SellingAndMarketingExpense": {
     "auth_ref": [],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss": {
       "order": 2.0,
       "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"
       }
      }
     },
     "localname": "SellingAndMarketingExpense",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SellingAndMarketingExpenseMember": {
     "auth_ref": [
      "r68"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Primary financial statement caption encompassing selling and marketing expense.",
        "label": "Selling and Marketing Expense [Member]",
        "terseLabel": "Sales and marketing"
       }
      }
     },
     "localname": "SellingAndMarketingExpenseMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ServiceLifeMember": {
     "auth_ref": [
      "r118"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "A revision in the estimated economic useful life of a long-lived tangible asset (the period of time over which the asset is projected to benefit operations).",
        "label": "Service Life [Member]",
        "terseLabel": "Service life"
       }
      }
     },
     "localname": "ServiceLifeMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SettledLitigationMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Agreement reached between parties in a litigation that occurs without judicial intervention, supervision or approval.",
        "label": "Settled Litigation [Member]",
        "terseLabel": "Settled Litigation"
       }
      }
     },
     "localname": "SettledLitigationMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesLegalMattersDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ShareBasedCompensation": {
     "auth_ref": [
      "r92"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows": {
       "order": 4.0,
       "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",
        "terseLabel": "Stock-based compensation",
        "verboseLabel": "Total stock-based compensation"
       }
      }
     },
     "localname": "ShareBasedCompensation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1": {
     "auth_ref": [
      "r282"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period",
        "terseLabel": "Award vesting period"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod": {
     "auth_ref": [
      "r293"
     ],
     "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",
        "negatedTerseLabel": "RSUs forfeited (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue": {
     "auth_ref": [
      "r298"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value",
        "terseLabel": "RSUs forfeited, weighted-average grant date fair value per share (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod": {
     "auth_ref": [
      "r296"
     ],
     "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": "RSUs granted (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue": {
     "auth_ref": [
      "r296"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The weighted average fair value at grant date for nonvested equity-based awards issued 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, Weighted Average Grant Date Fair Value",
        "verboseLabel": "Weighted average grant date fair value per share of RSUs granted (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber": {
     "auth_ref": [
      "r295"
     ],
     "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": "Outstanding, ending balance (in shares)",
        "periodStartLabel": "Outstanding, beginning balance (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue": {
     "auth_ref": [
      "r295"
     ],
     "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": "Outstanding, ending balance, weighted-average grant date fair value per share (in USD per share)",
        "periodStartLabel": "Outstanding, beginning balance, weighted-average grant date fair value per share (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward": {
     "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, Weighted Average Grant Date Fair Value [Abstract]",
        "terseLabel": "Weighted Average Grant Date Fair Value Per Share"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod": {
     "auth_ref": [
      "r297"
     ],
     "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",
        "negatedTerseLabel": "RSUs vested and released (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue": {
     "auth_ref": [
      "r301"
     ],
     "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",
        "terseLabel": "Total fair value of RSUs vested during the period"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue": {
     "auth_ref": [
      "r297"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value",
        "terseLabel": "RSUs vested and released, weighted-average grant date fair value per share (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate": {
     "auth_ref": [
      "r307"
     ],
     "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": "Dividend yield"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate": {
     "auth_ref": [
      "r306"
     ],
     "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": "Volatility"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate": {
     "auth_ref": [
      "r308"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails"
     ],
     "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"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails",
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate": {
     "auth_ref": [
      "r313"
     ],
     "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": "Maximum employee subscription rate, percentage of pre-tax earnings"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesPerEmployee": {
     "auth_ref": [
      "r313"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The highest quantity of shares an employee can purchase under the plan per period.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Per Employee",
        "terseLabel": "Maximum number of shares per employee per purchase period (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesPerEmployee",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward": {
     "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, Non-Option Equity Instruments, Outstanding [Roll Forward]",
        "terseLabel": "Number of Shares"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized": {
     "auth_ref": [
      "r284"
     ],
     "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": "Number of shares authorized for issuance (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "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": "Additional information pertaining to stock options"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber": {
     "auth_ref": [
      "r291"
     ],
     "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": "Exercisable (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice": {
     "auth_ref": [
      "r291"
     ],
     "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": "Exercisable, weighted-average exercise price (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue": {
     "auth_ref": [
      "r301"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod": {
     "auth_ref": [
      "r294"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "For presentations that combine terminations, 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 or that expired.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period",
        "negatedTerseLabel": "Options forfeited or expired (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice": {
     "auth_ref": [
      "r294"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Weighted average price of options that were either forfeited or expired.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price",
        "terseLabel": "Options forfeited or expired, weighted-average exercise price (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross": {
     "auth_ref": [],
     "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": "Options granted (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue": {
     "auth_ref": [
      "r300"
     ],
     "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 of options granted (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue": {
     "auth_ref": [
      "r313"
     ],
     "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": "Outstanding, Aggregate intrinsic value"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber": {
     "auth_ref": [
      "r290",
      "r313"
     ],
     "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": "Outstanding, ending balance (in shares)",
        "periodStartLabel": "Outstanding, beginning balance (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "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": "Number of Shares"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice": {
     "auth_ref": [
      "r289"
     ],
     "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": "Outstanding, ending balance, weighted-average exercise price (in USD per share)",
        "periodStartLabel": "Outstanding, beginning balance, weighted-average exercise price (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "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": "Weighted Average Exercise Price"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]",
        "terseLabel": "Vested and expected to vest as of December 31, 2019"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue": {
     "auth_ref": [
      "r302"
     ],
     "crdr": "debit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value",
        "terseLabel": "Vested and expected to vest, aggregate intrinsic value"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber": {
     "auth_ref": [
      "r303"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number",
        "terseLabel": "Vested and expected to vest (in shares)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice": {
     "auth_ref": [
      "r303"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price",
        "terseLabel": "Outstanding, weighted-average exercise price (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased": {
     "auth_ref": [
      "r278",
      "r313"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Per share weighted-average price paid for shares purchased on open market for issuance under share-based payment arrangement.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased",
        "terseLabel": "Weighted-average price per share (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain": {
     "auth_ref": [
      "r278",
      "r285"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Award under share-based payment arrangement.",
        "label": "Award Type [Domain]",
        "terseLabel": "Equity Award [Domain]"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCommonStockReservedforFutureIssuanceDetails",
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails",
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails",
      "http://www.five9.com/role/StockholdersEquityRSUActivitiesDetails",
      "http://www.five9.com/role/StockholdersEquityStockBasedCompensationDetails",
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice": {
     "auth_ref": [],
     "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": "Options exercised, weighted-average exercise price (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice": {
     "auth_ref": [],
     "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": "Options granted, weighted-average exercise price (in USD per share)"
       }
      }
     },
     "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_ShareBasedCompensationAwardTrancheOneMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "First portion of award under share-based payment arrangement differentiated by vesting feature, including, but not limited to, performance measure or service period.",
        "label": "Share-based Payment Arrangement, Tranche One [Member]",
        "terseLabel": "Tranche One"
       }
      }
     },
     "localname": "ShareBasedCompensationAwardTrancheOneMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_ShareBasedCompensationAwardTrancheTwoMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Second portion of award under share-based payment arrangement differentiated by vesting feature, including, but not limited to, performance measure or service period.",
        "label": "Share-based Payment Arrangement, Tranche Two [Member]",
        "terseLabel": "Tranche Two"
       }
      }
     },
     "localname": "ShareBasedCompensationAwardTrancheTwoMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SharePrice": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Price of a single share of a number of saleable stocks of a company.",
        "label": "Share Price",
        "verboseLabel": "Fair market value of common stock (in usd per share)"
       }
      }
     },
     "localname": "SharePrice",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "perShareItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage": {
     "auth_ref": [
      "r282"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Percentage of vesting of award under share-based payment arrangement.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage",
        "terseLabel": "Award vesting, percentage of award"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod": {
     "auth_ref": [
      "r283"
     ],
     "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": "Award expiration period"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1": {
     "auth_ref": [
      "r305",
      "r325"
     ],
     "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 (years)"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityOptionandESPPValuationAssumptionsDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1": {
     "auth_ref": [
      "r313"
     ],
     "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": "Exercisable, aggregate intrinsic value"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1": {
     "auth_ref": [
      "r313"
     ],
     "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": "Exercisable, weighted average remaining contractual life"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2": {
     "auth_ref": [
      "r303"
     ],
     "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 life"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1": {
     "auth_ref": [
      "r303"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term",
        "terseLabel": "Outstanding, weighted average remaining contractual life"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "durationItemType"
    },
    "us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1": {
     "auth_ref": [
      "r287"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.",
        "label": "Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value",
        "terseLabel": "Total fair value of options vested during the period"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "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": "Purchase price of shares, percentage of the fair market value of the Company's common stock"
       }
      }
     },
     "localname": "SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "xbrltype": "percentItemType"
    },
    "us-gaap_ShareholdersEquityAndShareBasedPaymentsTextBlock": {
     "auth_ref": [
      "r258",
      "r329"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The entire disclosure for shareholders' equity and share-based payment arrangement. Includes, but is not limited to, disclosure of policy and terms of share-based payment arrangement, deferred compensation arrangement, and employee stock purchase plan (ESPP).",
        "label": "Shareholders' Equity and Share-based Payments [Text Block]",
        "terseLabel": "Stockholders' Equity"
       }
      }
     },
     "localname": "ShareholdersEquityAndShareBasedPaymentsTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquity"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SharesIssued": {
     "auth_ref": [
      "r249"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.",
        "label": "Shares, Issued",
        "periodEndLabel": "Ending balance (in shares)",
        "periodStartLabel": "Beginning balance (in share)"
       }
      }
     },
     "localname": "SharesIssued",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_SoftwareDevelopmentMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Internally developed software for sale, licensing or long-term internal use.",
        "label": "Software Development [Member]",
        "terseLabel": "Internal-use software development costs",
        "verboseLabel": "Development costs"
       }
      }
     },
     "localname": "SoftwareDevelopmentMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPropertyandEquipmentNetDetails",
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofPropertyandEquipmentDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_StateAndLocalJurisdictionMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Designated tax department of a state or local government entitled to levy and collect income taxes from the entity.",
        "label": "State and Local Jurisdiction [Member]",
        "terseLabel": "State"
       }
      }
     },
     "localname": "StateAndLocalJurisdictionMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_StatementClassOfStockAxis": {
     "auth_ref": [
      "r16",
      "r17",
      "r18",
      "r249"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by the different classes of stock of the entity.",
        "label": "Class of Stock [Axis]",
        "terseLabel": "Class of Stock [Axis]"
       }
      }
     },
     "localname": "StatementClassOfStockAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityCapitalStructureDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementEquityComponentsAxis": {
     "auth_ref": [
      "r45",
      "r249"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by component of equity.",
        "label": "Equity Components [Axis]",
        "terseLabel": "Equity Components [Axis]"
       }
      }
     },
     "localname": "StatementEquityComponentsAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlowsParenthetical",
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementOfCashFlowsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Statement of Cash Flows [Abstract]",
        "terseLabel": "Statement of Cash Flows [Abstract]"
       }
      }
     },
     "localname": "StatementOfCashFlowsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementOfFinancialPositionAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Statement of Financial Position [Abstract]",
        "terseLabel": "Statement of Financial Position [Abstract]"
       }
      }
     },
     "localname": "StatementOfFinancialPositionAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementOfStockholdersEquityAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Statement of Stockholders' Equity [Abstract]",
        "terseLabel": "Statement of Stockholders' Equity [Abstract]"
       }
      }
     },
     "localname": "StatementOfStockholdersEquityAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_StatementTable": {
     "auth_ref": [],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows",
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofDepreciationandAmortizationExpenseDetails",
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedAllocationofStockBasedCompensationExpenseDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans": {
     "auth_ref": [
      "r17",
      "r18",
      "r249",
      "r257"
     ],
     "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": "Issuance of common stock under ESPP (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/StockholdersEquityESPPDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation": {
     "auth_ref": [
      "r17",
      "r18",
      "r249",
      "r257"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).",
        "label": "Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture",
        "terseLabel": "Issuance of common stock upon vesting of restricted stock units (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesShareBasedCompensation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised": {
     "auth_ref": [
      "r17",
      "r18",
      "r249",
      "r257",
      "r292"
     ],
     "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",
        "negatedTerseLabel": "Options exercised (in shares)",
        "terseLabel": "Issuance of common stock upon exercise of stock options (in shares)"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodSharesStockOptionsExercised",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/StockholdersEquityStockOptionActivitiesDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan": {
     "auth_ref": [
      "r17",
      "r18",
      "r249",
      "r257"
     ],
     "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": "Issuance of common stock under ESPP"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValueEmployeeStockPurchasePlan",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation": {
     "auth_ref": [
      "r17",
      "r18",
      "r257",
      "r280",
      "r300"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Value, after forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).",
        "label": "Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture",
        "terseLabel": "Issuance of common stock upon vesting of restricted stock units"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValueShareBasedCompensation",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised": {
     "auth_ref": [
      "r45",
      "r249",
      "r257"
     ],
     "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": "Issuance of common stock upon exercise of stock options"
       }
      }
     },
     "localname": "StockIssuedDuringPeriodValueStockOptionsExercised",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_StockholdersEquity": {
     "auth_ref": [
      "r18",
      "r22",
      "r23",
      "r162"
     ],
     "calculation": {
      "http://www.five9.com/role/ConsolidatedBalanceSheets": {
       "order": 2.0,
       "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",
        "totalLabel": "Total stockholders\u2019 equity"
       }
      }
     },
     "localname": "StockholdersEquity",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedBalanceSheets"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest": {
     "auth_ref": [
      "r375",
      "r376",
      "r381"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.",
        "label": "Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest",
        "periodEndLabel": "Ending balance",
        "periodStartLabel": "Beginning balance"
       }
      }
     },
     "localname": "StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_SubsequentEventLineItems": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.",
        "label": "Subsequent Event [Line Items]",
        "terseLabel": "Subsequent Event [Line Items]"
       }
      }
     },
     "localname": "SubsequentEventLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_SubsequentEventMember": {
     "auth_ref": [],
     "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"
       }
      }
     },
     "localname": "SubsequentEventMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SubsequentEventTable": {
     "auth_ref": [
      "r421"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Discloses pertinent information about one or more 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.",
        "label": "Subsequent Event [Table]",
        "terseLabel": "Subsequent Event [Table]"
       }
      }
     },
     "localname": "SubsequentEventTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_SubsequentEventTypeAxis": {
     "auth_ref": [
      "r421"
     ],
     "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 [Axis]"
       }
      }
     },
     "localname": "SubsequentEventTypeAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_SubsequentEventTypeDomain": {
     "auth_ref": [
      "r421"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "SubsequentEventTypeDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEventsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_SubsequentEventsAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Subsequent Events [Abstract]",
        "terseLabel": "Subsequent Events [Abstract]"
       }
      }
     },
     "localname": "SubsequentEventsAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "xbrltype": "stringItemType"
    },
    "us-gaap_SubsequentEventsTextBlock": {
     "auth_ref": [
      "r422"
     ],
     "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 Event"
       }
      }
     },
     "localname": "SubsequentEventsTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SubsequentEvents"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SupplementalBalanceSheetDisclosuresTextBlock": {
     "auth_ref": [
      "r49"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The entire disclosure for supplemental balance sheet disclosures, including descriptions and amounts for assets, liabilities, and equity.",
        "label": "Supplemental Balance Sheet Disclosures [Text Block]",
        "terseLabel": "Financial Statement Components"
       }
      }
     },
     "localname": "SupplementalBalanceSheetDisclosuresTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponents"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_SupplementalCashFlowInformationAbstract": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "label": "Supplemental Cash Flow Information [Abstract]",
        "terseLabel": "Supplemental disclosures of cash flow data:"
       }
      }
     },
     "localname": "SupplementalCashFlowInformationAbstract",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofCashFlows"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_TaxCreditCarryforwardAmount": {
     "auth_ref": [
      "r354"
     ],
     "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": "Research and development credit carryforwards"
       }
      }
     },
     "localname": "TaxCreditCarryforwardAmount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_TaxCreditCarryforwardAxis": {
     "auth_ref": [
      "r355"
     ],
     "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 [Axis]"
       }
      }
     },
     "localname": "TaxCreditCarryforwardAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_TaxCreditCarryforwardNameDomain": {
     "auth_ref": [
      "r355"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "The name of the tax credit carryforward.",
        "label": "Tax Credit Carryforward, Name [Domain]",
        "terseLabel": "Tax Credit Carryforward, Name [Domain]"
       }
      }
     },
     "localname": "TaxCreditCarryforwardNameDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain": {
     "auth_ref": [
      "r427"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Instrument or contract that imposes a contractual obligation to deliver cash or another financial instrument or to exchange other financial instruments on potentially unfavorable terms and conveys a contractual right to receive cash or another financial instrument or to exchange other financial instruments on potentially favorable terms.",
        "label": "Financial Instruments [Domain]",
        "terseLabel": "Financial Instruments [Domain]"
       }
      }
     },
     "localname": "TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_TypeOfAdoptionMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Adoption and early adoption of sources of change to generally accepted accounting principles (GAAP) in the United States. The FASB released the FASB Accounting Standards Codification as the authoritative source of literature effective for interim and annual periods ending after September 15, 2009. As part of the Codification process, the FASB issues Accounting Standards Updates to amend the Codification but otherwise the Accounting Standards Updates are not authoritative in their own right. All previous accounting standards (such as FASB Statements of Financial Accounting Standards, FASB Interpretations, FASB Staff Positions, Emerging Issues Task Force Consensuses, other pronouncements of the FASB or other designated bodies, or other forms of GAAP are considered accounting pronouncements) were superseded upon the adoption of the Codification. For an interim period, references to the superseded standards are included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.",
        "label": "Type of Adoption [Domain]",
        "terseLabel": "Type of Adoption [Domain]"
       }
      }
     },
     "localname": "TypeOfAdoptionMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ASC842AdoptionImpactBalanceSheetImpactsDetails",
      "http://www.five9.com/role/ASC842AdoptionImpactNarrativeDetails",
      "http://www.five9.com/role/ConsolidatedStatementsofStockholdersEquity",
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesRecentlyAdoptedAccountingPronouncementsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_USGovernmentAgenciesDebtSecuritiesMember": {
     "auth_ref": [
      "r271",
      "r437"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Debentures, notes, and other debt securities issued by US government agencies, for example, but not limited to, Government National Mortgage Association (GNMA or Ginnie Mae). Excludes US treasury securities and debt issued by government-sponsored Enterprises (GSEs), for example, but is not limited to, Federal Home Loan Mortgage Corporation (FHLMC or Freddie Mac), Federal National Mortgage Association (FNMA or Fannie Mae), and the Federal Home Loan Bank (FHLB).",
        "label": "US Government Agencies Debt Securities [Member]",
        "terseLabel": "U.S. agency securities"
       }
      }
     },
     "localname": "USGovernmentAgenciesDebtSecuritiesMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_USGovernmentCorporationsAndAgenciesSecuritiesMember": {
     "auth_ref": [
      "r440"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "This category includes information about debt issued by US Government Corporations and Agencies. Investments in such US Government Corporations may include debt securities issued by the Government National Mortgage Association (Ginnie Mae) and by the Federal National Mortgage Association (Fannie Mae) and the Federal Home Loan Mortgage Corporation (Freddie Mac).",
        "label": "US Government Corporations and Agencies Securities [Member]",
        "terseLabel": "U.S. agency securities and government sponsored securities"
       }
      }
     },
     "localname": "USGovernmentCorporationsAndAgenciesSecuritiesMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_USTreasurySecuritiesMember": {
     "auth_ref": [
      "r271",
      "r274",
      "r437"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "This category includes information about debt securities issued by the United States Department of the Treasury and backed by the United States government. Such securities primarily consist of treasury bills (short-term maturities - one year or less), treasury notes (intermediate term maturities - two to ten years), and treasury bonds (long-term maturities - ten to thirty years).",
        "label": "US Treasury Securities [Member]",
        "terseLabel": "U.S. treasury"
       }
      }
     },
     "localname": "USTreasurySecuritiesMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofAssetsCarriedatFairValueDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofContinuousUnrealizedLossPositionDetails",
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsScheduleofMarketableInvestmentsDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_UnbilledRevenuesMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Unbilled amounts due for services rendered or products shipped. This element is distinct from unbilled contracts receivables because this is based on noncontract transactions.",
        "label": "Unbilled Revenues [Member]",
        "terseLabel": "Unbilled trade accounts receivable, net of advance client deposits"
       }
      }
     },
     "localname": "UnbilledRevenuesMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/FinancialStatementComponentsScheduleofAccountsReceivableDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain": {
     "auth_ref": [
      "r218"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "General description of the goods or services to be purchased from the counterparty to the unconditional purchase arrangement.",
        "label": "Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain]",
        "terseLabel": "Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain]"
       }
      }
     },
     "localname": "UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_UnrealizedGainLossOnInvestmentsTableTextBlock": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Tabular disclosure of unrealized gains and losses on investments.",
        "label": "Unrealized Gain (Loss) on Investments [Table Text Block]",
        "terseLabel": "Schedule of gross unrealized losses and fair value of marketable investments"
       }
      }
     },
     "localname": "UnrealizedGainLossOnInvestmentsTableTextBlock",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/InvestmentsandFairValueMeasurementsTables"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_UnrecognizedTaxBenefits": {
     "auth_ref": [
      "r335",
      "r342"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of unrecognized tax benefits.",
        "label": "Unrecognized Tax Benefits",
        "periodEndLabel": "Unrecognized benefit \u2014 end of period",
        "periodStartLabel": "Unrecognized benefit \u2014 beginning of period"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefits",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofUnrecognizedTaxBenefitsRollforwardDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions": {
     "auth_ref": [
      "r343"
     ],
     "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",
        "negatedTerseLabel": "Gross decreases \u2014 prior year tax positions"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofUnrecognizedTaxBenefitsRollforwardDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions": {
     "auth_ref": [
      "r344"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.",
        "label": "Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions",
        "terseLabel": "Gross increases \u2014 current year tax positions"
       }
      }
     },
     "localname": "UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesScheduleofUnrecognizedTaxBenefitsRollforwardDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis": {
     "auth_ref": [
      "r216",
      "r217"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Pertinent information about unrecorded unconditional purchase arrangements to acquire goods or services, by category of goods or services. arrangements to acquire goods or services, by category of goods or services.",
        "label": "Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis]",
        "terseLabel": "Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis]"
       }
      }
     },
     "localname": "UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_UnrecordedUnconditionalPurchaseObligationLineItems": {
     "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": "Unrecorded Unconditional Purchase Obligation [Line Items]",
        "terseLabel": "Unrecorded Unconditional Purchase Obligation [Line Items]"
       }
      }
     },
     "localname": "UnrecordedUnconditionalPurchaseObligationLineItems",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_UnrecordedUnconditionalPurchaseObligationTable": {
     "auth_ref": [
      "r216",
      "r217"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Describes each unrecorded unconditional purchase obligation arrangement to purchase goods and services that extend over multiple periods, any assets pledged to secure payment, and the fixed or determinable amount of payments due in each of the next five years and thereafter.",
        "label": "Unrecorded Unconditional Purchase Obligation [Table]",
        "terseLabel": "Unrecorded Unconditional Purchase Obligation [Table]"
       }
      }
     },
     "localname": "UnrecordedUnconditionalPurchaseObligationTable",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/CommitmentsandContingenciesHostingTelecommunicationsUsageandMaintenanceServicesDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_UseOfEstimates": {
     "auth_ref": [
      "r141",
      "r142",
      "r144",
      "r145",
      "r146",
      "r147",
      "r148"
     ],
     "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/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesPolicies"
     ],
     "xbrltype": "textBlockItemType"
    },
    "us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount": {
     "auth_ref": [
      "r336"
     ],
     "crdr": "credit",
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.",
        "label": "Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount",
        "terseLabel": "Increase (decrease) in valuation allowance for deferred tax assets"
       }
      }
     },
     "localname": "ValuationAllowanceDeferredTaxAssetChangeInAmount",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/IncomeTaxesNarrativeDetails"
     ],
     "xbrltype": "monetaryItemType"
    },
    "us-gaap_VariableRateAxis": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by type of variable rate.",
        "label": "Variable Rate [Axis]",
        "terseLabel": "Variable Rate [Axis]"
       }
      }
     },
     "localname": "VariableRateAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "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 [Domain]"
       }
      }
     },
     "localname": "VariableRateDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/Debt2016LoanandSecurityAgreementDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_VestingAxis": {
     "auth_ref": [
      "r313"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Information by vesting schedule of award under share-based payment arrangement.",
        "label": "Vesting [Axis]",
        "terseLabel": "Vesting [Axis]"
       }
      }
     },
     "localname": "VestingAxis",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "stringItemType"
    },
    "us-gaap_VestingDomain": {
     "auth_ref": [
      "r313"
     ],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Vesting schedule of award under share-based payment arrangement.",
        "label": "Vesting [Domain]",
        "terseLabel": "Vesting [Domain]"
       }
      }
     },
     "localname": "VestingDomain",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/StockholdersEquityEquityIncentivePlansDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_WarrantMember": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Security that gives the holder the right to purchase shares of stock in accordance with the terms of the instrument, usually upon payment of a specified amount.",
        "label": "Warrant [Member]",
        "verboseLabel": "Common stock warrants"
       }
      }
     },
     "localname": "WarrantMember",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/NetLossPerShareAntidilutiveSecuritiesExcludedfromComputationofDilutedNetLossPerShareDetails"
     ],
     "xbrltype": "domainItemType"
    },
    "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding": {
     "auth_ref": [
      "r123",
      "r127"
     ],
     "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": "Diluted (in shares)"
       }
      }
     },
     "localname": "WeightedAverageNumberOfDilutedSharesOutstanding",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted": {
     "auth_ref": [],
     "lang": {
      "en-US": {
       "role": {
        "documentation": "Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).",
        "label": "Weighted Average Number of Shares Outstanding, Basic and Diluted",
        "terseLabel": "Basic and diluted (in shares)",
        "verboseLabel": "Weighted-average shares used in computing basic and diluted net loss per share (in shares)"
       }
      }
     },
     "localname": "WeightedAverageNumberOfShareOutstandingBasicAndDiluted",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/ConsolidatedStatementsofOperationsandComprehensiveLoss",
      "http://www.five9.com/role/NetLossPerShareBasicandDilutedNetLossPerShareDetails"
     ],
     "xbrltype": "sharesItemType"
    },
    "us-gaap_WeightedAverageNumberOfSharesOutstandingBasic": {
     "auth_ref": [
      "r122",
      "r127"
     ],
     "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": "Basic (in shares)"
       }
      }
     },
     "localname": "WeightedAverageNumberOfSharesOutstandingBasic",
     "nsuri": "http://fasb.org/us-gaap/2019-01-31",
     "presentation": [
      "http://www.five9.com/role/SelectedQuarterlyFinancialDataUnauditedScheduleofQuarterlyFinancialInformationDetails"
     ],
     "xbrltype": "sharesItemType"
    }
   },
   "unitCount": 6
  }
 },
 "std_ref": {
  "r0": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "205",
   "URI": "http://asc.fasb.org/topic&trid=2122149"
  },
  "r1": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765"
  },
  "r10": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(14))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r100": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586"
  },
  "r101": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586"
  },
  "r102": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=84158767&loc=d3e18726-107790"
  },
  "r103": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790"
  },
  "r104": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=84158767&loc=d3e18823-107790"
  },
  "r105": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(h)(2))",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690"
  },
  "r106": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08(h))",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690"
  },
  "r107": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08.(d),(e))",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690"
  },
  "r108": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08.(e),(f))",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690"
  },
  "r109": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08.(f))",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690"
  },
  "r11": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(19))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r110": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08.(h)(1)(i))",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690"
  },
  "r111": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.4-08.(h))",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690"
  },
  "r112": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.12-04.(a))",
   "Topic": "235",
   "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690"
  },
  "r113": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "235",
   "URI": "http://asc.fasb.org/topic&trid=2122369"
  },
  "r114": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "18",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "http://asc.fasb.org/extlink&oid=115929471&loc=d3e21843-107793"
  },
  "r115": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22499-107794"
  },
  "r116": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794"
  },
  "r117": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22583-107794"
  },
  "r118": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22595-107794"
  },
  "r119": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22644-107794"
  },
  "r12": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(20))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r120": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22658-107794"
  },
  "r121": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "250",
   "URI": "http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794"
  },
  "r122": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1448-109256"
  },
  "r123": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "16",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1505-109256"
  },
  "r124": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1252-109256"
  },
  "r125": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "60B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=SL5780133-109256"
  },
  "r126": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1337-109256"
  },
  "r127": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257"
  },
  "r128": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257"
  },
  "r129": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257"
  },
  "r13": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(22))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r130": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=6371337&loc=d3e3630-109257"
  },
  "r131": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "52",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "260",
   "URI": "http://asc.fasb.org/extlink&oid=117327953&loc=d3e4984-109258"
  },
  "r132": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "260",
   "URI": "http://asc.fasb.org/topic&trid=2144383"
  },
  "r133": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "270",
   "URI": "http://asc.fasb.org/extlink&oid=116846552&loc=d3e725-108305"
  },
  "r134": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "270",
   "URI": "http://asc.fasb.org/extlink&oid=116846552&loc=d3e765-108305"
  },
  "r135": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "270",
   "URI": "http://asc.fasb.org/extlink&oid=116846552&loc=d3e777-108305"
  },
  "r136": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "270",
   "URI": "http://asc.fasb.org/extlink&oid=118952077&loc=d3e1280-108306"
  },
  "r137": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.10-01(a)(5))",
   "Topic": "270",
   "URI": "http://asc.fasb.org/extlink&oid=27015980&loc=d3e46468-122699"
  },
  "r138": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.10-01.(a)(5))",
   "Topic": "270",
   "URI": "http://asc.fasb.org/extlink&oid=27015980&loc=d3e46468-122699"
  },
  "r139": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.10-01.(b)(6))",
   "Topic": "270",
   "URI": "http://asc.fasb.org/extlink&oid=27015980&loc=d3e46468-122699"
  },
  "r14": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(26)(a))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r140": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "270",
   "URI": "http://asc.fasb.org/topic&trid=2126967"
  },
  "r141": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "275",
   "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592"
  },
  "r142": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "275",
   "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592"
  },
  "r143": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "275",
   "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592"
  },
  "r144": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6161-108592"
  },
  "r145": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6191-108592"
  },
  "r146": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6061-108592"
  },
  "r147": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6132-108592"
  },
  "r148": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "275",
   "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6143-108592"
  },
  "r149": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "275",
   "URI": "http://asc.fasb.org/topic&trid=2134479"
  },
  "r15": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(26)(b))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r150": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "280",
   "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599"
  },
  "r151": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "280",
   "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599"
  },
  "r152": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)",
   "Topic": "280",
   "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599"
  },
  "r153": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "22",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599"
  },
  "r154": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "41",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "280",
   "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e9038-108599"
  },
  "r155": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "280",
   "URI": "http://asc.fasb.org/topic&trid=2134510"
  },
  "r156": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "http://asc.fasb.org/extlink&oid=118952595&loc=d3e4647-111522"
  },
  "r157": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522"
  },
  "r158": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "http://asc.fasb.org/extlink&oid=118952595&loc=d3e4531-111522"
  },
  "r159": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11B",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "310",
   "URI": "http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524"
  },
  "r16": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(27))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r160": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524"
  },
  "r161": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "310",
   "URI": "http://asc.fasb.org/extlink&oid=118936363&loc=d3e5144-111524"
  },
  "r162": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 4.E)",
   "Topic": "310",
   "URI": "http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707"
  },
  "r163": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562"
  },
  "r164": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118954083&loc=d3e26853-111562"
  },
  "r165": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118954083&loc=d3e26626-111562"
  },
  "r166": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563"
  },
  "r167": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(aa)",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563"
  },
  "r168": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563"
  },
  "r169": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563"
  },
  "r17": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(28))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r170": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563"
  },
  "r171": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "320",
   "URI": "http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563"
  },
  "r172": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "320",
   "URI": "http://asc.fasb.org/topic&trid=2196928"
  },
  "r173": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446"
  },
  "r174": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919244-210447"
  },
  "r175": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447"
  },
  "r176": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447"
  },
  "r177": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(f)",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447"
  },
  "r178": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447"
  },
  "r179": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919253-210447"
  },
  "r18": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(29))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r180": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "16",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447"
  },
  "r181": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447"
  },
  "r182": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454"
  },
  "r183": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(2)",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=118955579&loc=SL82922888-210455"
  },
  "r184": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=118955579&loc=SL82922888-210455"
  },
  "r185": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455"
  },
  "r186": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=118955579&loc=SL82922895-210455"
  },
  "r187": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=118955579&loc=SL82922900-210455"
  },
  "r188": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "30",
   "Topic": "326",
   "URI": "http://asc.fasb.org/extlink&oid=118942371&loc=SL82922954-210456"
  },
  "r189": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "05",
   "SubTopic": "10",
   "Topic": "340",
   "URI": "http://asc.fasb.org/extlink&oid=68074540&loc=d3e5879-108316"
  },
  "r19": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(3))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r190": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Subparagraph": "(b)",
   "Topic": "340",
   "URI": "http://asc.fasb.org/extlink&oid=68051541&loc=SL49131251-203054"
  },
  "r191": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "40",
   "Subparagraph": "(a)",
   "Topic": "340",
   "URI": "http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054"
  },
  "r192": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266"
  },
  "r193": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975"
  },
  "r194": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267"
  },
  "r195": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(h)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267"
  },
  "r196": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267"
  },
  "r197": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274"
  },
  "r198": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274"
  },
  "r199": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275"
  },
  "r2": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765"
  },
  "r20": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(30)(a)(1))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r200": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(1)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275"
  },
  "r201": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(d)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275"
  },
  "r202": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275"
  },
  "r203": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "((a)(1),(b))",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275"
  },
  "r204": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275"
  },
  "r205": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(1)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275"
  },
  "r206": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(2)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275"
  },
  "r207": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(a)(3)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275"
  },
  "r208": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(d)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275"
  },
  "r209": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "350",
   "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275"
  },
  "r21": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(30)(a)(3))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r210": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "350",
   "URI": "http://asc.fasb.org/topic&trid=2144416"
  },
  "r211": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "360",
   "URI": "http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229"
  },
  "r212": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "360",
   "URI": "http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229"
  },
  "r213": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "360",
   "URI": "http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229"
  },
  "r214": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "360",
   "URI": "http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229"
  },
  "r215": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "360",
   "URI": "http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230"
  },
  "r216": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "440",
   "URI": "http://asc.fasb.org/extlink&oid=77896938&loc=d3e25287-109308"
  },
  "r217": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "440",
   "URI": "http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308"
  },
  "r218": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "440",
   "URI": "http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308"
  },
  "r219": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "440",
   "URI": "http://asc.fasb.org/topic&trid=2144648"
  },
  "r22": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(30))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r220": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349"
  },
  "r221": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14615-108349"
  },
  "r222": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14394-108349"
  },
  "r223": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349"
  },
  "r224": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349"
  },
  "r225": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14453-108349"
  },
  "r226": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14472-108349"
  },
  "r227": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14557-108349"
  },
  "r228": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "450",
   "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14557-108349"
  },
  "r229": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "450",
   "URI": "http://asc.fasb.org/topic&trid=2127136"
  },
  "r23": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(31))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r230": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "15",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "460",
   "URI": "http://asc.fasb.org/extlink&oid=99404985&loc=d3e10037-110241"
  },
  "r231": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "460",
   "URI": "http://asc.fasb.org/extlink&oid=118943654&loc=d3e12021-110248"
  },
  "r232": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "460",
   "URI": "http://asc.fasb.org/extlink&oid=118943654&loc=d3e12053-110248"
  },
  "r233": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "460",
   "URI": "http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249"
  },
  "r234": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "460",
   "URI": "http://asc.fasb.org/extlink&oid=118956092&loc=d3e13051-110250"
  },
  "r235": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=99376301&loc=SL5988623-112600"
  },
  "r236": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601"
  },
  "r237": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=6802200&loc=SL6230698-112601"
  },
  "r238": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "20",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=109126253&loc=d3e4852-112606"
  },
  "r239": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870"
  },
  "r24": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(32))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r240": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)(1)",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870"
  },
  "r241": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)(3)",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870"
  },
  "r242": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870"
  },
  "r243": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870"
  },
  "r244": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "470",
   "URI": "http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870"
  },
  "r245": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "470",
   "URI": "http://asc.fasb.org/topic&trid=2208564"
  },
  "r246": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(CFRR 211.02)",
   "Topic": "480",
   "URI": "http://asc.fasb.org/extlink&oid=65877616&loc=d3e177068-122764"
  },
  "r247": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=65888546&loc=d3e21300-112643"
  },
  "r248": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21553-112644"
  },
  "r249": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644"
  },
  "r25": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(4))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r250": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644"
  },
  "r251": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21484-112644"
  },
  "r252": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21488-112644"
  },
  "r253": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644"
  },
  "r254": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644"
  },
  "r255": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644"
  },
  "r256": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21538-112644"
  },
  "r257": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.3-04)",
   "Topic": "505",
   "URI": "http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770"
  },
  "r258": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "505",
   "URI": "http://asc.fasb.org/topic&trid=2208762"
  },
  "r259": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044"
  },
  "r26": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(7))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r260": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118944033&loc=SL49130532-203044"
  },
  "r261": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118944033&loc=SL49130533-203044"
  },
  "r262": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130551-203045"
  },
  "r263": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045"
  },
  "r264": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045"
  },
  "r265": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045"
  },
  "r266": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045"
  },
  "r267": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045"
  },
  "r268": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "91",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=118944142&loc=SL49130690-203046-203046"
  },
  "r269": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Topic": "606",
   "URI": "http://asc.fasb.org/extlink&oid=113356391&loc=SL49131195-203048"
  },
  "r27": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(8))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r270": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "606",
   "URI": "http://asc.fasb.org/topic&trid=49130388"
  },
  "r271": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)(ii)",
   "Topic": "715",
   "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920"
  },
  "r272": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(d)(iv)(01)",
   "Topic": "715",
   "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920"
  },
  "r273": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(e)",
   "Topic": "715",
   "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920"
  },
  "r274": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "715",
   "URI": "http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921"
  },
  "r275": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "70",
   "Topic": "715",
   "URI": "http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942"
  },
  "r276": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "715",
   "URI": "http://asc.fasb.org/topic&trid=2235017"
  },
  "r277": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "35",
   "SubTopic": "10",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116855982&loc=d3e4534-113899"
  },
  "r278": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901"
  },
  "r279": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901"
  },
  "r28": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.1)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r280": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901"
  },
  "r281": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901"
  },
  "r282": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(1)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r283": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r284": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(3)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r285": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a),(g)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r286": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b),(f(1))",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r287": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r288": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r289": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(i)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r29": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.13(a))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r290": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(i)-(ii)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r291": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iii)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r292": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(2)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r293": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(3)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r294": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(1)(iv)(3)-(4)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r295": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(i)-(ii)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r296": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(1)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r297": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(2)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r298": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(2)(iii)(3)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r299": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r3": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765"
  },
  "r30": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.13)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r300": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)(1)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r301": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(d)(2)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r302": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r303": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)(1)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r304": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r305": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(i)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r306": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(ii)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r307": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(iii)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r308": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(f)(2)(iv)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r309": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r31": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.14)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r310": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)(1)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r311": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)(1)(i)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r312": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(i)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r313": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901"
  },
  "r314": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116856206&loc=SL79508275-113901"
  },
  "r315": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79507997-165333"
  },
  "r316": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79507997-165333"
  },
  "r317": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79508013-165333"
  },
  "r318": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79508013-165333"
  },
  "r319": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79508029-165333"
  },
  "r32": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.17)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r320": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79508029-165333"
  },
  "r321": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79508043-165333"
  },
  "r322": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79508043-165333"
  },
  "r323": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79508057-165333"
  },
  "r324": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=116863282&loc=SL79508057-165333"
  },
  "r325": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 14.D.2)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809"
  },
  "r326": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 14.F)",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809"
  },
  "r327": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=118258462&loc=d3e11149-113907"
  },
  "r328": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "718",
   "URI": "http://asc.fasb.org/extlink&oid=118258462&loc=d3e11178-113907"
  },
  "r329": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "718",
   "URI": "http://asc.fasb.org/topic&trid=2228938"
  },
  "r33": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.19(a))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r330": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "35",
   "Subparagraph": "(a)",
   "Topic": "720",
   "URI": "http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848"
  },
  "r331": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "35",
   "Subparagraph": "(b)",
   "Topic": "720",
   "URI": "http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848"
  },
  "r332": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "730",
   "URI": "http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373"
  },
  "r333": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=117330534&loc=d3e28680-109314"
  },
  "r334": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=117330534&loc=d3e28680-109314"
  },
  "r335": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=116821951&loc=SL37586934-109318"
  },
  "r336": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=116821951&loc=d3e32123-109318"
  },
  "r337": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=116821951&loc=d3e32247-109318"
  },
  "r338": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=116821951&loc=d3e32280-109318"
  },
  "r339": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319"
  },
  "r34": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.19(b),22(b))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r340": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319"
  },
  "r341": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319"
  },
  "r342": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319"
  },
  "r343": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(1)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319"
  },
  "r344": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)(2)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319"
  },
  "r345": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319"
  },
  "r346": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32809-109319"
  },
  "r347": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "19",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32840-109319"
  },
  "r348": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319"
  },
  "r349": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319"
  },
  "r35": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.19-26)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r350": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b),(c)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319"
  },
  "r351": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319"
  },
  "r352": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319"
  },
  "r353": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32847-109319"
  },
  "r354": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319"
  },
  "r355": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319"
  },
  "r356": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319"
  },
  "r357": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319"
  },
  "r358": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319"
  },
  "r359": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "9",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319"
  },
  "r36": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.20)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r360": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "217",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=117331294&loc=d3e36027-109320"
  },
  "r361": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "51",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=117331294&loc=d3e34017-109320"
  },
  "r362": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB TOPIC 6.I)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817"
  },
  "r363": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SAB Topic 6.I.7)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817"
  },
  "r364": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324"
  },
  "r365": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "05",
   "SubTopic": "30",
   "Topic": "740",
   "URI": "http://asc.fasb.org/extlink&oid=65884525&loc=d3e40913-109327"
  },
  "r366": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "740",
   "URI": "http://asc.fasb.org/topic&trid=2144680"
  },
  "r367": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "805",
   "URI": "http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463"
  },
  "r368": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "805",
   "URI": "http://asc.fasb.org/extlink&oid=79982066&loc=d3e1486-128463"
  },
  "r369": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "31",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Subparagraph": "(h)",
   "Topic": "805",
   "URI": "http://asc.fasb.org/extlink&oid=77890550&loc=d3e5419-128473"
  },
  "r37": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.21)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r370": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "38",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "805",
   "URI": "http://asc.fasb.org/extlink&oid=77890550&loc=d3e5504-128473"
  },
  "r371": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "38",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "805",
   "URI": "http://asc.fasb.org/extlink&oid=77890550&loc=d3e5504-128473"
  },
  "r372": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "7",
   "Publisher": "FASB",
   "Section": "30",
   "SubTopic": "30",
   "Topic": "805",
   "URI": "http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477"
  },
  "r373": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "30",
   "SubTopic": "30",
   "Topic": "805",
   "URI": "http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477"
  },
  "r374": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Subparagraph": "(b)",
   "Topic": "805",
   "URI": "http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479"
  },
  "r375": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4568447-111683"
  },
  "r376": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "16",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4568740-111683"
  },
  "r377": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "19",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683"
  },
  "r378": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "20",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4569643-111683"
  },
  "r379": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c)(3)",
   "Topic": "810",
   "URI": "http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684"
  },
  "r38": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.22(a)(1))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r380": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(c),(3)",
   "Topic": "810",
   "URI": "http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684"
  },
  "r381": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4I",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "10",
   "Topic": "810",
   "URI": "http://asc.fasb.org/extlink&oid=116874947&loc=SL4590271-111686"
  },
  "r382": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "810",
   "URI": "http://asc.fasb.org/topic&trid=2197479"
  },
  "r383": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "820",
   "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258"
  },
  "r384": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "820",
   "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258"
  },
  "r385": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(bb)",
   "Topic": "820",
   "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258"
  },
  "r386": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(bbb)(1)",
   "Topic": "820",
   "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258"
  },
  "r387": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(bbb)(2)",
   "Topic": "820",
   "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258"
  },
  "r388": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Subparagraph": "(h)",
   "Topic": "820",
   "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258"
  },
  "r389": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "820",
   "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19279-110258"
  },
  "r39": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.22(a)(5))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r390": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6A",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "820",
   "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258"
  },
  "r391": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "825",
   "URI": "http://asc.fasb.org/extlink&oid=118260190&loc=d3e13467-108611"
  },
  "r392": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "830",
   "URI": "http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895"
  },
  "r393": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "230",
   "Topic": "830",
   "URI": "http://asc.fasb.org/extlink&oid=98513438&loc=d3e33268-110906"
  },
  "r394": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "30",
   "Topic": "830",
   "URI": "http://asc.fasb.org/extlink&oid=6450520&loc=d3e32583-110901"
  },
  "r395": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "835",
   "URI": "http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391"
  },
  "r396": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399"
  },
  "r397": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399"
  },
  "r398": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399"
  },
  "r399": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "30",
   "Topic": "835",
   "URI": "http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400"
  },
  "r4": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765"
  },
  "r40": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.22)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r400": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "20",
   "Topic": "840",
   "URI": "http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707"
  },
  "r401": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "65",
   "SubTopic": "10",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=119364159&loc=SL77916155-209984"
  },
  "r402": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977"
  },
  "r403": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977"
  },
  "r404": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977"
  },
  "r405": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977"
  },
  "r406": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "20",
   "Subparagraph": "(c)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977"
  },
  "r407": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)(3)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980"
  },
  "r408": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980"
  },
  "r409": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980"
  },
  "r41": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.24)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r410": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(a)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980"
  },
  "r411": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(b)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980"
  },
  "r412": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)(1)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980"
  },
  "r413": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)(2)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980"
  },
  "r414": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)(3)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980"
  },
  "r415": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(g)(4)",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980"
  },
  "r416": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980"
  },
  "r417": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "6",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980"
  },
  "r418": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "53",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971"
  },
  "r419": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "SubTopic": "20",
   "Topic": "842",
   "URI": "http://asc.fasb.org/subtopic&trid=77888251"
  },
  "r42": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.25)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r420": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "850",
   "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39599-107864"
  },
  "r421": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "855",
   "URI": "http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662"
  },
  "r422": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "855",
   "URI": "http://asc.fasb.org/topic&trid=2122774"
  },
  "r423": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(bb)",
   "Topic": "860",
   "URI": "http://asc.fasb.org/extlink&oid=118948506&loc=d3e107207-111719"
  },
  "r424": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(bb)(1)",
   "Topic": "860",
   "URI": "http://asc.fasb.org/extlink&oid=118948506&loc=d3e107207-111719"
  },
  "r425": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(bb)(2)",
   "Topic": "860",
   "URI": "http://asc.fasb.org/extlink&oid=118948506&loc=d3e107207-111719"
  },
  "r426": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Subparagraph": "(bb)(3)",
   "Topic": "860",
   "URI": "http://asc.fasb.org/extlink&oid=118948506&loc=d3e107207-111719"
  },
  "r427": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "50",
   "Topic": "860",
   "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746"
  },
  "r428": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "340",
   "Topic": "928",
   "URI": "http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004"
  },
  "r429": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "20",
   "Topic": "940",
   "URI": "http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953"
  },
  "r43": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.28,29)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r430": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "20",
   "Topic": "940",
   "URI": "http://asc.fasb.org/extlink&oid=68072869&loc=d3e41256-110953"
  },
  "r431": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "25",
   "SubTopic": "20",
   "Topic": "940",
   "URI": "http://asc.fasb.org/extlink&oid=68072869&loc=d3e41261-110953"
  },
  "r432": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(11))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r433": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(13))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r434": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(15)(2))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r435": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(16))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r436": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(23))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r437": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03(6)(a)(1))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r438": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03.15(5))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r439": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03.17)",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r44": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.29)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r440": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.9-03.6(a)(1))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878"
  },
  "r441": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04(15))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260"
  },
  "r442": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04(22))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260"
  },
  "r443": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04(23))",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260"
  },
  "r444": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.9-04.9)",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260"
  },
  "r445": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "320",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=75019621&loc=d3e62652-112803"
  },
  "r446": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "405",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818"
  },
  "r447": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "470",
   "Subparagraph": "e",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823"
  },
  "r448": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "470",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823"
  },
  "r449": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "825",
   "Topic": "942",
   "URI": "http://asc.fasb.org/extlink&oid=108315417&loc=d3e61044-112788"
  },
  "r45": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.29-31)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r450": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(15)(b)(2))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r451": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(16))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r452": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(12))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r453": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(16))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r454": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(23)(a)(4))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r455": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(25))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r456": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03(a)(8))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r457": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03.(a),19)",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r458": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "210",
   "Subparagraph": "(SX 210.7-03.15(a))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910"
  },
  "r459": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(18))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263"
  },
  "r46": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.3,4)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r460": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(19))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263"
  },
  "r461": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "220",
   "Subparagraph": "(SX 210.7-04(8))",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263"
  },
  "r462": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13H",
   "Publisher": "FASB",
   "Section": "55",
   "SubTopic": "40",
   "Subparagraph": "(b)",
   "Topic": "944",
   "URI": "http://asc.fasb.org/extlink&oid=117419784&loc=SL117783719-158441"
  },
  "r463": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "310",
   "Subparagraph": "(SX 210.12-29(Footnote 4))",
   "Topic": "948",
   "URI": "http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014"
  },
  "r464": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "740",
   "Topic": "954",
   "URI": "http://asc.fasb.org/extlink&oid=6491622&loc=d3e9504-115650"
  },
  "r465": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "360",
   "Subparagraph": "(SX 210.12-28(Footnote 2))",
   "Topic": "970",
   "URI": "http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024"
  },
  "r466": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "20",
   "Topic": "985",
   "URI": "http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756"
  },
  "r467": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "b"
  },
  "r468": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "b-23"
  },
  "r469": {
   "Name": "Exchange Act",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "d1-1"
  },
  "r47": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.8)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r470": {
   "Name": "Forms 10-K, 10-Q, 20-F",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "13",
   "Subsection": "a-1-"
  },
  "r471": {
   "Name": "Forms 10-K, 20-F, 40-F",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "15",
   "Subsection": "d-1"
  },
  "r472": {
   "Name": "Regulation 12B",
   "Number": "240",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "b-2"
  },
  "r473": {
   "Name": "Regulation S-K (SK)",
   "Number": "229",
   "Paragraph": "(a)",
   "Publisher": "SEC",
   "Section": "303",
   "Subparagraph": "(5)"
  },
  "r474": {
   "Name": "Regulation S-T",
   "Number": "232",
   "Publisher": "SEC",
   "Section": "405"
  },
  "r475": {
   "Footnote": "2",
   "Name": "Regulation S-X (SX)",
   "Number": "210",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "28"
  },
  "r476": {
   "Footnote": "4",
   "Name": "Regulation S-X (SX)",
   "Number": "210",
   "Publisher": "SEC",
   "Section": "12",
   "Subsection": "29"
  },
  "r48": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02.9)",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r49": {
   "Name": "Accounting Standards Codification",
   "Publisher": "FASB",
   "Topic": "210",
   "URI": "http://asc.fasb.org/topic&trid=2122208"
  },
  "r5": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6787-107765"
  },
  "r50": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "10A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580"
  },
  "r51": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580"
  },
  "r52": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=d3e681-108580"
  },
  "r53": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669686-108580"
  },
  "r54": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL34724394-108580"
  },
  "r55": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580"
  },
  "r56": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580"
  },
  "r57": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1A",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580"
  },
  "r58": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580"
  },
  "r59": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1B",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580"
  },
  "r6": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6801-107765"
  },
  "r60": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "5",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=118930883&loc=d3e557-108580"
  },
  "r61": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116657188&loc=SL116659661-227067"
  },
  "r62": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.3-03(e))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868656-224227"
  },
  "r63": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(210.5-03(11))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r64": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(1))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r65": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(10))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r66": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(20))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r67": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(21))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r68": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(4))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r69": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(5))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r7": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "8",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6935-107765"
  },
  "r70": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03(8))",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r71": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.1)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r72": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.1,2)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r73": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.2)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r74": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.4)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r75": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.7)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r76": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.8)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r77": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-03.9)",
   "Topic": "220",
   "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227"
  },
  "r78": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "11",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3151-108585"
  },
  "r79": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "12",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585"
  },
  "r8": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(1))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r80": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585"
  },
  "r81": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "13",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(c)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585"
  },
  "r82": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585"
  },
  "r83": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "14",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585"
  },
  "r84": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585"
  },
  "r85": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585"
  },
  "r86": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "15",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585"
  },
  "r87": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "17",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(d)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585"
  },
  "r88": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "24",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3521-108585"
  },
  "r89": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(e)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585"
  },
  "r9": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "S99",
   "SubTopic": "10",
   "Subparagraph": "(SX 210.5-02(13))",
   "Topic": "210",
   "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682"
  },
  "r90": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(g)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585"
  },
  "r91": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "25",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585"
  },
  "r92": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(a)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585"
  },
  "r93": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Subparagraph": "(b)",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585"
  },
  "r94": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "28",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585"
  },
  "r95": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "45",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3044-108585"
  },
  "r96": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "1",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=98513485&loc=d3e4273-108586"
  },
  "r97": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "2",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586"
  },
  "r98": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "3",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586"
  },
  "r99": {
   "Name": "Accounting Standards Codification",
   "Paragraph": "4",
   "Publisher": "FASB",
   "Section": "50",
   "SubTopic": "10",
   "Topic": "230",
   "URI": "http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586"
  }
 },
 "version": "2.1"
}
