{ "instance": { "nmrk-10q_20190930.htm": { "axisCustom": 0, "axisStandard": 53, "contextCount": 651, "dts": { "calculationLink": { "local": [ "nmrk-20190930_cal.xml" ] }, "definitionLink": { "local": [ "nmrk-20190930_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": [ "nmrk-10q_20190930.htm" ] }, "labelLink": { "local": [ "nmrk-20190930_lab.xml" ], "remote": [ "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": [ "nmrk-20190930_pre.xml" ] }, "referenceLink": { "remote": [ "https://xbrl.sec.gov/dei/2019/dei-ref-2019-01-31.xml", "http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-ref-2019-01-31.xml" ] }, "schema": { "local": [ "nmrk-20190930.xsd" ], "remote": [ "http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd", "http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd", "http://www.xbrl.org/2003/xl-2003-12-31.xsd", "http://www.xbrl.org/2003/xlink-2003-12-31.xsd", "http://www.xbrl.org/2005/xbrldt-2005.xsd", "https://xbrl.sec.gov/country/2017/country-2017-01-31.xsd", "http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd", "https://xbrl.sec.gov/currency/2019/currency-2019-01-31.xsd", "https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd", "http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd", "https://xbrl.sec.gov/exch/2019/exch-2019-01-31.xsd", "https://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd", "http://www.xbrl.org/lrr/arcrole/factExplanatory-2009-12-16.xsd", "http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd", "http://www.xbrl.org/lrr/role/net-2009-12-16.xsd", "https://xbrl.sec.gov/naics/2017/naics-2017-01-31.xsd", "https://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd", "http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.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/srt/2019/elts/srt-roles-2019-01-31.xsd", "https://xbrl.sec.gov/stpr/2018/stpr-2018-01-31.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/us-gaap/2019/elts/us-types-2019-01-31.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", "http://www.xbrl.org/lrr/role/deprecated-2009-12-16.xsd" ] } }, "elementCount": 994, "entityCount": 1, "hidden": { "http://fasb.org/us-gaap/2019-01-31": 61, "http://www.ngkf.com/20190930": 8, "http://xbrl.sec.gov/dei/2019-01-31": 5, "total": 74 }, "keyCustom": 161, "keyStandard": 508, "memberCustom": 99, "memberStandard": 55, "nsprefix": "nmrk", "nsuri": "http://www.ngkf.com/20190930", "report": { "R1": { "firstAnchor": { "ancestors": [ "p", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "dei:DocumentType", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "document", "isDefault": "true", "longName": "100000 - Document - Document and Entity Information", "role": "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation", "shortName": "Document and Entity Information", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "p", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "dei:DocumentType", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R10": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100090 - Disclosure - Organization and Basis of Presentation", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentation", "shortName": "Organization and Basis of Presentation", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R100": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181231", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:OperatingLeasesFutureMinimumPaymentsRemainderOfFiscalYear", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101000 - Disclosure - Leases - Schedule of Future Minimum Rental Payments for Operating Leases (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail", "shortName": "Leases - Schedule of Future Minimum Rental Payments for Operating Leases (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181231", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:OperatingLeasesFutureMinimumPaymentsRemainderOfFiscalYear", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R101": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfOtherCurrentAssetsTableTextBlock", "us-gaap:OtherAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DerivativeAssetsCurrent", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101010 - Disclosure - Other Current and Non-current Assets - Summary of Other Current Assets (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail", "shortName": "Other Current and Non-current Assets - Summary of Other Current Assets (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfOtherCurrentAssetsTableTextBlock", "us-gaap:OtherAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DerivativeAssetsCurrent", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R102": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfOtherAssetsNoncurrentTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:OperatingLeaseRightOfUseAsset", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101020 - Disclosure - Other Current and Non-current Assets - Summary of Non-current Other Assets (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail", "shortName": "Other Current and Non-current Assets - Summary of Non-current Other Assets (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfOtherAssetsNoncurrentTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:DeferredTaxAssetsLiabilitiesNet", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R103": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:SecuritiesLoaned", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101030 - Disclosure - Securities Loaned - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail", "shortName": "Securities Loaned - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "nmrk:SecuritiesLoanedDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapRelatedPartyTransactionsByRelatedPartyAxis_nmrkCantorFitzgeraldCoMember_20190930", "decimals": "-5", "lang": null, "name": "us-gaap:SecuritiesLoaned", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R104": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:WarehouseAgreementBorrowings", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101040 - Disclosure - Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises - Schedule of Company Lines Available and Borrowings Outstanding (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "shortName": "Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises - Schedule of Company Lines Available and Borrowings Outstanding (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfLineOfCreditFacilitiesTextBlock", "nmrk:WarehouseLinesOfCreditTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapCreditFacilityAxis_nmrkCommittedLinesMember_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:LineOfCreditFacilityCapacityAvailableForSpecificPurposeOtherThanForTradePurchases", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R105": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfLineOfCreditFacilitiesTextBlock", "nmrk:WarehouseLinesOfCreditTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapDebtInstrumentAxis_nmrkWarehouseFacilityDueJuneSeventeenTwoThousandTwentyMember_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DebtInstrumentMaturityDate", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101050 - Disclosure - Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises - Schedule of Company Lines Available and Borrowings Outstanding (Parenthetical) (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail", "shortName": "Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises - Schedule of Company Lines Available and Borrowings Outstanding (Parenthetical) (Detail)", "subGroupType": "parenthetical", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfLineOfCreditFacilitiesTextBlock", "nmrk:WarehouseLinesOfCreditTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapDebtInstrumentAxis_nmrkWarehouseFacilityDueJuneSeventeenTwoThousandTwentyMember_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DebtInstrumentMaturityDate", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R106": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:LongTermDebtNoncurrent", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101060 - Disclosure - Long-Term Debt (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "shortName": "Long-Term Debt (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfDebtTableTextBlock", "us-gaap:DebtDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapDebtInstrumentAxis_us-gaapRevolvingCreditFacilityMember_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:LongTermDebtNoncurrent", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R107": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfDebtTableTextBlock", "us-gaap:DebtDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapDebtInstrumentAxis_nmrkSixPointOneTwoFivePercentSeniorNotesMember_20190930", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:DebtInstrumentInterestRateStatedPercentage", "reportCount": 1, "unitRef": "U_xbrlipure", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101070 - Disclosure - Long-Term Debt (Parenthetical) (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtParentheticalDetail", "shortName": "Long-Term Debt (Parenthetical) (Detail)", "subGroupType": "parenthetical", "uniqueAnchor": null }, "R108": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:LongTermDebtNoncurrent", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101080 - Disclosure - Long-Term Debt - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "shortName": "Long-Term Debt - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapCreditFacilityAxis_us-gaapRevolvingCreditFacilityMember_20190701_20190930", "decimals": "-5", "lang": null, "name": "us-gaap:AmortizationOfFinancingCosts", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R109": { "firstAnchor": { "ancestors": [ "p", "nmrk:CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapManagingRisksInherentInServicingAssetsAndServicingLiabilitiesByTypeOfRiskAxis_us-gaapCreditRiskMember_20190930", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:GuaranteeObligationsMaximumExposure", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101090 - Disclosure - Financial Guarantee Liability - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "shortName": "Financial Guarantee Liability - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtCounterpartyNameAxis_nmrkFannieMaeAndFreddieMacMember_us-gaapManagingRisksInherentInServicingAssetsAndServicingLiabilitiesByTypeOfRiskAxis_us-gaapCreditRiskMember_20190930", "decimals": "-8", "lang": null, "name": "us-gaap:FinancialServicesLiabilities", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R11": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PartnersCapitalNotesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100100 - Disclosure - Limited Partnership Interests", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterests", "shortName": "Limited Partnership Interests", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PartnersCapitalNotesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R110": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfGuaranteeObligationsTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181231", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:GuarantyLiabilities", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101100 - Disclosure - Financial Guarantee Liability - Summary of Changes in Estimated Liability Under Guarantee Liability (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfChangesInEstimatedLiabilityUnderGuaranteeLiabilityDetail", "shortName": "Financial Guarantee Liability - Summary of Changes in Estimated Liability Under Guarantee Liability (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfGuaranteeObligationsTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20180101_20181231", "decimals": "-3", "lang": null, "name": "nmrk:GuarantyLiabilitiesReversalToProvision", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R111": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "nmrk:IncreaseDecreaseToFinancialGuaranteeLiability", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101110 - Disclosure - Financial Guarantee Liability - Summary of Provisions for Risk Sharing (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail", "shortName": "Financial Guarantee Liability - Summary of Provisions for Risk Sharing (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "nmrk:IncreaseDecreaseToFinancialGuaranteeLiability", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R112": { "firstAnchor": { "ancestors": [ "p", "us-gaap:ConcentrationRiskDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtStatementGeographicalAxis_stprCA_us-gaapConcentrationRiskByBenchmarkAxis_us-gaapLiabilitiesTotalMember_us-gaapConcentrationRiskByTypeAxis_us-gaapCreditConcentrationRiskMember_us-gaapInvestmentTypeAxis_nmrkFannieMaeDUSAndFreddieMacTAHLoansMember_20190101_20190930", "decimals": "2", "first": true, "lang": null, "name": "us-gaap:ConcentrationRiskPercentage1", "reportCount": 1, "unique": true, "unitRef": "U_xbrlipure", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101120 - Disclosure - Concentrations of Credit Risk - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail", "shortName": "Concentrations of Credit Risk - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:ConcentrationRiskDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtStatementGeographicalAxis_stprCA_us-gaapConcentrationRiskByBenchmarkAxis_us-gaapLiabilitiesTotalMember_us-gaapConcentrationRiskByTypeAxis_us-gaapCreditConcentrationRiskMember_us-gaapInvestmentTypeAxis_nmrkFannieMaeDUSAndFreddieMacTAHLoansMember_20190101_20190930", "decimals": "2", "first": true, "lang": null, "name": "us-gaap:ConcentrationRiskPercentage1", "reportCount": 1, "unique": true, "unitRef": "U_xbrlipure", "xsiNil": "false" } }, "R113": { "firstAnchor": { "ancestors": [ "p", "nmrk:EscrowAndCustodialFundsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-8", "first": true, "lang": null, "name": "us-gaap:EscrowDeposit", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101130 - Disclosure - Escrow and Custodial Funds - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEscrowAndCustodialFundsAdditionalInformationDetail", "shortName": "Escrow and Custodial Funds - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "nmrk:EscrowAndCustodialFundsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-8", "first": true, "lang": null, "name": "us-gaap:EscrowDeposit", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R114": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:MarketableSecuritiesCurrent", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101140 - Disclosure - Fair Value of Financial Assets and Liabilities - Fair Value Hierarchy of Financial Assets and Liabilities under U.S. GAAP Guidance (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "shortName": "Fair Value of Financial Assets and Liabilities - Fair Value Hierarchy of Financial Assets and Liabilities under U.S. GAAP Guidance (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "us-gaap:FairValueDisclosuresTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:AssetsFairValueDisclosure", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R115": { "firstAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:FairValueAssetsLevel1ToLevel2TransfersAmount", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101150 - Disclosure - Fair Value of Financial Assets and Liabilities - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "shortName": "Fair Value of Financial Assets and Liabilities - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:FairValueAssetsLevel1ToLevel2TransfersAmount", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R116": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190630", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101160 - Disclosure - Fair Value of Financial Assets and Liabilities - Changes in Level 3 Nasdaq Forwards, Rate Lock Commitments, Forwards and Contingent Consideration Measured at Fair Value on Recurring Basis (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "shortName": "Fair Value of Financial Assets and Liabilities - Changes in Level 3 Nasdaq Forwards, Rate Lock Commitments, Forwards and Contingent Consideration Measured at Fair Value on Recurring Basis (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R117": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101170 - Disclosure - Fair Value of Financial Assets and Liabilities - Quantitative Information about Level 3 Fair Value Measurements (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "shortName": "Fair Value of Financial Assets and Liabilities - Quantitative Information about Level 3 Fair Value Measurements (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:FairValueOptionQuantitativeDisclosuresTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtRangeAxis_srtWeightedAverageMember_us-gaapBalanceSheetLocationAxis_us-gaapAccountsPayableAndAccruedLiabilitiesMember_us-gaapContingentConsiderationByTypeAxis_nmrkContingentConsiderationLiabilityMember_us-gaapMeasurementInputTypeAxis_us-gaapMeasurementInputDiscountRateMember_20190930", "decimals": "3", "lang": null, "name": "us-gaap:BusinessCombinationContingentConsiderationLiabilityMeasurementInput", "reportCount": 1, "unique": true, "unitRef": "U_xbrlipure", "xsiNil": "false" } }, "R118": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101180 - Disclosure - Related Party Transactions - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "shortName": "Related Party Transactions - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190205_20190206", "decimals": "4", "lang": null, "name": "nmrk:DeterminationPrice", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD_xbrlishares", "xsiNil": "false" } }, "R119": { "firstAnchor": { "ancestors": [ "span", "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101190 - Disclosure - Income Taxes - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureIncomeTaxesAdditionalInformationDetail", "shortName": "Income Taxes - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R12": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:SignificantAccountingPoliciesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100110 - Disclosure - Summary of Significant Accounting Policies", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPolicies", "shortName": "Summary of Significant Accounting Policies", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:SignificantAccountingPoliciesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R120": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:ScheduleOfAccountsPayableAccruedLiabilitiesAndOtherLiabilitiesCurrentTableTextBlock", "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "nmrk:AccountsPayableAndAccruedExpensesCurrent", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101200 - Disclosure - Accounts Payable, Accrued Expenses and Other Liabilities - Components of Current Portion of Accounts Payable, Accrued Expenses and Other Liabilities (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail", "shortName": "Accounts Payable, Accrued Expenses and Other Liabilities - Components of Current Portion of Accounts Payable, Accrued Expenses and Other Liabilities (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:ScheduleOfAccountsPayableAccruedLiabilitiesAndOtherLiabilitiesCurrentTableTextBlock", "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "nmrk:AccountsPayableAndAccruedExpensesCurrent", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R121": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:OtherNoncurrentLiabilitiesTableTextBlock", "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:OperatingLeaseLiabilityNoncurrent", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101210 - Disclosure - Accounts Payable, Accrued Expenses and Other Liabilities - Components of Other Liabilities (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail", "shortName": "Accounts Payable, Accrued Expenses and Other Liabilities - Components of Other Liabilities (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:OtherNoncurrentLiabilitiesTableTextBlock", "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "lang": null, "name": "nmrk:AccruedPayrollTaxesNoncurrent", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R122": { "firstAnchor": { "ancestors": [ "p", "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101220 - Disclosure - Compensation - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "shortName": "Compensation - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R123": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfShareBasedCompensationActivityTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_deiLegalEntityAxis_nmrkBGCHoldingsLimitedPartnershipMember_us-gaapPartnerTypeOfPartnersCapitalAccountAxis_nmrkLimitedPartnershipUnitsMember_20181231", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber", "reportCount": 1, "unitRef": "U_xbrlishares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101230 - Disclosure - Compensation - Activity Associated with Limited Partnership Units (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "shortName": "Compensation - Activity Associated with Limited Partnership Units (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfShareBasedCompensationActivityTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_deiLegalEntityAxis_nmrkBGCHoldingsLimitedPartnershipMember_us-gaapPartnerTypeOfPartnersCapitalAccountAxis_nmrkLimitedPartnershipUnitsMember_20190101_20190930", "decimals": "INF", "lang": null, "name": "nmrk:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentRedeemedExchanged", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R124": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:ScheduleOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostInitialPublicOfferingGrantsTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtConsolidatedEntitiesAxis_nmrkNewmarkHoldingsLimitedPartnershipMember_us-gaapPartnerTypeOfPartnersCapitalAccountAxis_nmrkShareEquivalentLimitedPartnershipUnitsMember_20181231", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber", "reportCount": 1, "unitRef": "U_xbrlishares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101240 - Disclosure - Compensation - Summary of Activity of Number of Share Equivalent Limited Partnership Units and Post IPO Grants (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail", "shortName": "Compensation - Summary of Activity of Number of Share Equivalent Limited Partnership Units and Post IPO Grants (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:ScheduleOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostInitialPublicOfferingGrantsTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtConsolidatedEntitiesAxis_nmrkNewmarkHoldingsLimitedPartnershipMember_us-gaapPartnerTypeOfPartnersCapitalAccountAxis_nmrkShareEquivalentLimitedPartnershipUnitsMember_20190101_20190930", "decimals": "INF", "lang": null, "name": "nmrk:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentRedeemedExchanged", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R125": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtConsolidatedEntitiesAxis_nmrkNewmarkHoldingsLimitedPartnershipMember_us-gaapAwardTypeAxis_us-gaapRestrictedStockUnitsRSUMember_20181231", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber", "reportCount": 1, "unitRef": "U_xbrlishares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101250 - Disclosure - Compensation - Activity Associated with Restricted Stock Units (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "shortName": "Compensation - Activity Associated with Restricted Stock Units (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtConsolidatedEntitiesAxis_nmrkNewmarkHoldingsLimitedPartnershipMember_us-gaapAwardTypeAxis_us-gaapRestrictedStockUnitsRSUMember_20190101_20190930", "decimals": "INF", "lang": null, "name": "us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R126": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:OtherNoncurrentLiabilitiesTableTextBlock", "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101260 - Disclosure - Commitments and Contingencies - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail", "shortName": "Commitments and Contingencies - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapBusinessAcquisitionAxis_nmrkAcquisitionsFromTwoThousandFourteenThroughTwoThousandNineteenMember_20190930", "decimals": "-5", "lang": null, "name": "us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R127": { "firstAnchor": { "ancestors": [ "p", "us-gaap:SubsequentEventsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapSubsequentEventTypeAxis_us-gaapSubsequentEventMember_20191029_20191029", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:CommonStockDividendsPerShareDeclared", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD_xbrlishares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "101270 - Disclosure - Subsequent Events - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail", "shortName": "Subsequent Events - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:SubsequentEventsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapSubsequentEventTypeAxis_us-gaapSubsequentEventMember_20191029_20191029", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:CommonStockDividendsPerShareDeclared", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD_xbrlishares", "xsiNil": "false" } }, "R13": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:BusinessCombinationDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100120 - Disclosure - Acquisitions", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitions", "shortName": "Acquisitions", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:BusinessCombinationDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R14": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:EarningsPerShareTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100130 - Disclosure - Earnings Per Share and Weighted-Average Shares Outstanding", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstanding", "shortName": "Earnings Per Share and Weighted-Average Shares Outstanding", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:EarningsPerShareTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R15": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:StockholdersEquityNoteDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100140 - Disclosure - Stock Transactions and Unit Redemptions", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptions", "shortName": "Stock Transactions and Unit Redemptions", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:StockholdersEquityNoteDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R16": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100150 - Disclosure - Marketable Securities", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecurities", "shortName": "Marketable Securities", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R17": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:EquityMethodInvestmentsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100160 - Disclosure - Investments", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestments", "shortName": "Investments", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:EquityMethodInvestmentsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R18": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:BrokersAndDealersDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100170 - Disclosure - Capital and Liquidity Requirements", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirements", "shortName": "Capital and Liquidity Requirements", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:BrokersAndDealersDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R19": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:FinancingReceivablesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100180 - Disclosure - Loans Held for Sale, at Fair Value", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValue", "shortName": "Loans Held for Sale, at Fair Value", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:FinancingReceivablesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R2": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:CashAndCashEquivalentsAtCarryingValue", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "100010 - Statement - Condensed Consolidated Balance Sheets", "role": "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "shortName": "Condensed Consolidated Balance Sheets", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:CashAndCashEquivalentsAtCarryingValue", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R20": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100190 - Disclosure - Derivatives", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivatives", "shortName": "Derivatives", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R21": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100200 - Disclosure - Credit Enhancement Receivable, Contingent Liability and Credit Enhancement Deposit", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDeposit", "shortName": "Credit Enhancement Receivable, Contingent Liability and Credit Enhancement Deposit", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R22": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:RevenueFromContractWithCustomerTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100210 - Disclosure - Revenues from Contracts with Customers", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomers", "shortName": "Revenues from Contracts with Customers", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:RevenueFromContractWithCustomerTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R23": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:GainsFromMortgageBankingActivitiesOriginationsNetTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100220 - Disclosure - Gains from Mortgage Banking Activities/Originations, Net", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNet", "shortName": "Gains from Mortgage Banking Activities/Originations, Net", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:GainsFromMortgageBankingActivitiesOriginationsNetTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R24": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:MortgageServicingRightsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100230 - Disclosure - Mortgage Servicing Rights, Net (\"MSRs\")", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrs", "shortName": "Mortgage Servicing Rights, Net (\"MSRs\")", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:MortgageServicingRightsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R25": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100240 - Disclosure - Goodwill and Other Intangible Assets, Net", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNet", "shortName": "Goodwill and Other Intangible Assets, Net", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R26": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100250 - Disclosure - Fixed Assets, Net", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNet", "shortName": "Fixed Assets, Net", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R27": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LesseeOperatingLeasesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100260 - Disclosure - Leases", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeases", "shortName": "Leases", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LesseeOperatingLeasesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R28": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:OtherAssetsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100270 - Disclosure - Other Current and Non-current Assets", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssets", "shortName": "Other Current and Non-current Assets", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:OtherAssetsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R29": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:SecuritiesLoanedDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100280 - Disclosure - Securities Loaned", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoaned", "shortName": "Securities Loaned", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:SecuritiesLoanedDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R3": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapStatementClassOfStockAxis_us-gaapCommonClassAMember_20190930", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:CommonStockParOrStatedValuePerShare", "reportCount": 1, "unitRef": "U_iso4217USD_xbrlishares", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "100020 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)", "role": "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical", "shortName": "Condensed Consolidated Balance Sheets (Parenthetical)", "subGroupType": "parenthetical", "uniqueAnchor": null }, "R30": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:WarehouseLinesOfCreditTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100290 - Disclosure - Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprises", "shortName": "Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:WarehouseLinesOfCreditTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R31": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DebtDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100300 - Disclosure - Long-Term Debt", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebt", "shortName": "Long-Term Debt", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DebtDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R32": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:GuaranteesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100310 - Disclosure - Financial Guarantee Liability", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiability", "shortName": "Financial Guarantee Liability", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:GuaranteesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R33": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ConcentrationRiskDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100320 - Disclosure - Concentrations of Credit Risk", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRisk", "shortName": "Concentrations of Credit Risk", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ConcentrationRiskDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R34": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:EscrowAndCustodialFundsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100330 - Disclosure - Escrow and Custodial Funds", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEscrowAndCustodialFunds", "shortName": "Escrow and Custodial Funds", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:EscrowAndCustodialFundsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R35": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:FairValueDisclosuresTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100340 - Disclosure - Fair Value of Financial Assets and Liabilities", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilities", "shortName": "Fair Value of Financial Assets and Liabilities", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:FairValueDisclosuresTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R36": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:RelatedPartyTransactionsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100350 - Disclosure - Related Party Transactions", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactions", "shortName": "Related Party Transactions", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:RelatedPartyTransactionsDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R37": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:IncomeTaxDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100360 - Disclosure - Income Taxes", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureIncomeTaxes", "shortName": "Income Taxes", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:IncomeTaxDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R38": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100370 - Disclosure - Accounts Payable, Accrued Expenses and Other Liabilities", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilities", "shortName": "Accounts Payable, Accrued Expenses and Other Liabilities", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R39": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100380 - Disclosure - Compensation", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensation", "shortName": "Compensation", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R4": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "100030 - Statement - Condensed Consolidated Statements of Operations", "role": "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations", "shortName": "Condensed Consolidated Statements of Operations", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:CostDirectLabor", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R40": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100390 - Disclosure - Commitments and Contingencies", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingencies", "shortName": "Commitments and Contingencies", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:CommitmentsAndContingenciesDisclosureTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R41": { "firstAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:SubsequentEventsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100400 - Disclosure - Subsequent Events", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEvents", "shortName": "Subsequent Events", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:SubsequentEventsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R42": { "firstAnchor": { "ancestors": [ "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:BasisOfAccountingPolicyPolicyTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100410 - Disclosure - Organization and Basis of Presentation (Policies)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationPolicies", "shortName": "Organization and Basis of Presentation (Policies)", "subGroupType": "policies", "uniqueAnchor": { "ancestors": [ "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:BasisOfAccountingPolicyPolicyTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R43": { "firstAnchor": { "ancestors": [ "p", "us-gaap:SegmentReportingPolicyPolicyTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100420 - Disclosure - Summary of Significant Accounting Policies (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesTables", "shortName": "Summary of Significant Accounting Policies (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:SegmentReportingPolicyPolicyTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R44": { "firstAnchor": { "ancestors": [ "us-gaap:BusinessCombinationDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100430 - Disclosure - Acquisitions (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsTables", "shortName": "Acquisitions (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:BusinessCombinationDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R45": { "firstAnchor": { "ancestors": [ "us-gaap:EarningsPerShareTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfEarningsPerShareBasicByCommonClassTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100440 - Disclosure - Earnings Per Share and Weighted-Average Shares Outstanding (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingTables", "shortName": "Earnings Per Share and Weighted-Average Shares Outstanding (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:EarningsPerShareTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfEarningsPerShareBasicByCommonClassTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R46": { "firstAnchor": { "ancestors": [ "us-gaap:StockholdersEquityNoteDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfCommonStockOutstandingRollForwardTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100450 - Disclosure - Stock Transactions and Unit Redemptions (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsTables", "shortName": "Stock Transactions and Unit Redemptions (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:StockholdersEquityNoteDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfCommonStockOutstandingRollForwardTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R47": { "firstAnchor": { "ancestors": [ "p", "us-gaap:FinancingReceivablesTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:ScheduleOfLoansHeldForSaleTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100460 - Disclosure - Loans Held for Sale, at Fair Value (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueTables", "shortName": "Loans Held for Sale, at Fair Value (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:FinancingReceivablesTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:ScheduleOfLoansHeldForSaleTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R48": { "firstAnchor": { "ancestors": [ "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100470 - Disclosure - Derivatives (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesTables", "shortName": "Derivatives (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R49": { "firstAnchor": { "ancestors": [ "us-gaap:RevenueFromContractWithCustomerTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:ScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100480 - Disclosure - Revenues from Contracts with Customers (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersTables", "shortName": "Revenues from Contracts with Customers (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:RevenueFromContractWithCustomerTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:ScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R5": { "firstAnchor": { "ancestors": [ "link:footnote", "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-5", "first": true, "lang": "en-US", "name": "us-gaap:PreferredStockDividendsIncomeStatementImpact", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "100040 - Statement - Condensed Consolidated Statements of Operations (Parenthetical)", "role": "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperationsParenthetical", "shortName": "Condensed Consolidated Statements of Operations (Parenthetical)", "subGroupType": "parenthetical", "uniqueAnchor": null }, "R50": { "firstAnchor": { "ancestors": [ "nmrk:GainsFromMortgageBankingActivitiesOriginationsNetTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:SummaryOfGainsFromMortgageBankingActivitiesNetTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100490 - Disclosure - Gains from Mortgage Banking Activities/Originations, Net (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetTables", "shortName": "Gains from Mortgage Banking Activities/Originations, Net (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "nmrk:GainsFromMortgageBankingActivitiesOriginationsNetTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:SummaryOfGainsFromMortgageBankingActivitiesNetTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R51": { "firstAnchor": { "ancestors": [ "nmrk:MortgageServicingRightsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfServicingAssetsAtAmortizedValueTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100500 - Disclosure - Mortgage Servicing Rights, Net (\"MSRs\") (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsTables", "shortName": "Mortgage Servicing Rights, Net (\"MSRs\") (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "nmrk:MortgageServicingRightsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfServicingAssetsAtAmortizedValueTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R52": { "firstAnchor": { "ancestors": [ "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfGoodwillTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100510 - Disclosure - Goodwill and Other Intangible Assets, Net (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetTables", "shortName": "Goodwill and Other Intangible Assets, Net (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfGoodwillTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R53": { "firstAnchor": { "ancestors": [ "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PropertyPlantAndEquipmentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100520 - Disclosure - Fixed Assets, Net (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetTables", "shortName": "Fixed Assets, Net (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:PropertyPlantAndEquipmentTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R54": { "firstAnchor": { "ancestors": [ "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100530 - Disclosure - Leases (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesTables", "shortName": "Leases (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R55": { "firstAnchor": { "ancestors": [ "us-gaap:OtherAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfOtherCurrentAssetsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100540 - Disclosure - Other Current and Non-current Assets (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsTables", "shortName": "Other Current and Non-current Assets (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:OtherAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfOtherCurrentAssetsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R56": { "firstAnchor": { "ancestors": [ "nmrk:WarehouseLinesOfCreditTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfLineOfCreditFacilitiesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100550 - Disclosure - Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesTables", "shortName": "Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "nmrk:WarehouseLinesOfCreditTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfLineOfCreditFacilitiesTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R57": { "firstAnchor": { "ancestors": [ "us-gaap:DebtDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfDebtTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100560 - Disclosure - Long-Term Debt (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtTables", "shortName": "Long-Term Debt (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "us-gaap:DebtDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfDebtTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R58": { "firstAnchor": { "ancestors": [ "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfGuaranteeObligationsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100570 - Disclosure - Financial Guarantee Liability (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityTables", "shortName": "Financial Guarantee Liability (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfGuaranteeObligationsTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R59": { "firstAnchor": { "ancestors": [ "p", "us-gaap:FairValueDisclosuresTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100580 - Disclosure - Fair Value of Financial Assets and Liabilities (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesTables", "shortName": "Fair Value of Financial Assets and Liabilities (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:FairValueDisclosuresTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R6": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:ProfitLoss", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "100050 - Statement - Condensed Consolidated Statements of Comprehensive Income", "role": "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome", "shortName": "Condensed Consolidated Statements of Comprehensive Income", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R60": { "firstAnchor": { "ancestors": [ "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:ScheduleOfAccountsPayableAccruedLiabilitiesAndOtherLiabilitiesCurrentTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100590 - Disclosure - Accounts Payable, Accrued Expenses and Other Liabilities (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesTables", "shortName": "Accounts Payable, Accrued Expenses and Other Liabilities (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:ScheduleOfAccountsPayableAccruedLiabilitiesAndOtherLiabilitiesCurrentTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R61": { "firstAnchor": { "ancestors": [ "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:ScheduleOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostInitialPublicOfferingGrantsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100600 - Disclosure - Compensation (Tables)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables", "shortName": "Compensation (Tables)", "subGroupType": "tables", "uniqueAnchor": { "ancestors": [ "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:ScheduleOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostInitialPublicOfferingGrantsTableTextBlock", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R62": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfOtherAssetsNoncurrentTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:EquityMethodInvestments", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100610 - Disclosure - Organization and Basis of Presentation - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "shortName": "Organization and Basis of Presentation - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181129_20181130", "decimals": "-5", "lang": null, "name": "nmrk:NumberOfUnitsConvertedToCommonStock", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R63": { "firstAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:PostTerminationAwardPayoutPeriod", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100620 - Disclosure - Limited Partnership Interests - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "shortName": "Limited Partnership Interests - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:PostTerminationAwardPayoutPeriod", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R64": { "firstAnchor": { "ancestors": [ "p", "us-gaap:LesseeLeasesPolicyTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LesseeOperatingLeaseOptionToExtend", "reportCount": 1, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100630 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail", "shortName": "Summary of Significant Accounting Policies - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": null }, "R65": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100640 - Disclosure - Summary of Significant Accounting Policies - Schedule of Recognized Revenues (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail", "shortName": "Summary of Significant Accounting Policies - Schedule of Recognized Revenues (Detail)", "subGroupType": "details", "uniqueAnchor": null }, "R66": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:OtherNoncurrentLiabilitiesTableTextBlock", "nmrk:AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181231", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100650 - Disclosure - Acquisitions - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "shortName": "Acquisitions - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20180101_20181231", "decimals": "-5", "lang": null, "name": "us-gaap:BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R67": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:Goodwill", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100660 - Disclosure - Acquisitions - Summary of Components of Purchase Consideration Transferred and Preliminary Allocation of Assets Acquired and Liabilities Assumed (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail", "shortName": "Acquisitions - Summary of Components of Purchase Consideration Transferred and Preliminary Allocation of Assets Acquired and Liabilities Assumed (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock", "us-gaap:BusinessCombinationDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapBusinessAcquisitionAxis_nmrkTwoThousandNineteenAcquisitionsMember_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R68": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100670 - Disclosure - Earnings Per Share and Weighted-Average Shares Outstanding - Calculation of Basic Earnings Per Share (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfBasicEarningsPerShareDetail", "shortName": "Earnings Per Share and Weighted-Average Shares Outstanding - Calculation of Basic Earnings Per Share (Detail)", "subGroupType": "details", "uniqueAnchor": null }, "R69": { "firstAnchor": { "ancestors": [ "link:footnote", "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-5", "first": true, "lang": "en-US", "name": "us-gaap:PreferredStockDividendsIncomeStatementImpact", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100680 - Disclosure - Earnings Per Share and Weighted-Average Shares Outstanding - Calculation of Basic Earnings Per Share (Parenthetical) (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfBasicEarningsPerShareParentheticalDetail", "shortName": "Earnings Per Share and Weighted-Average Shares Outstanding - Calculation of Basic Earnings Per Share (Parenthetical) (Detail)", "subGroupType": "parenthetical", "uniqueAnchor": null }, "R7": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20171231", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "100060 - Statement - Condensed Consolidated Statements of Changes in Equity", "role": "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "shortName": "Condensed Consolidated Statements of Changes in Equity", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20171231", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R70": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100690 - Disclosure - Earnings Per Share and Weighted-Average Shares Outstanding - Calculation of Fully Diluted Earnings Per Share (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail", "shortName": "Earnings Per Share and Weighted-Average Shares Outstanding - Calculation of Fully Diluted Earnings Per Share (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfEarningsPerShareDilutedByCommonClassTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "lang": null, "name": "nmrk:AllocationOfIncomeLossToLimitedPartnershipInterestDiluted", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R71": { "firstAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100700 - Disclosure - Earnings Per Share and Weighted-Average Shares Outstanding - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingAdditionalInformationDetail", "shortName": "Earnings Per Share and Weighted-Average Shares Outstanding - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R72": { "firstAnchor": { "ancestors": [ "p", "us-gaap:StockholdersEquityNoteDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "INF", "first": true, "lang": null, "name": "nmrk:NumberOfAuthorizedClassesOfCommonStock", "reportCount": 1, "unitRef": "U_xbrlishares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100710 - Disclosure - Stock Transactions and Unit Redemptions - Additional Information (Details)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "shortName": "Stock Transactions and Unit Redemptions - Additional Information (Details)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:StockholdersEquityNoteDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapStatementClassOfStockAxis_us-gaapCommonClassAMember_20190101_20190930", "decimals": null, "lang": "en-US", "name": "us-gaap:CommonStockVotingRights", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R73": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfCommonStockOutstandingRollForwardTableTextBlock", "us-gaap:StockholdersEquityNoteDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapStatementClassOfStockAxis_us-gaapCommonClassAMember_20190630", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:CommonStockSharesOutstanding", "reportCount": 1, "unitRef": "U_xbrlishares", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100720 - Disclosure - Stock Transactions and Unit Redemptions - Schedule of Changes in Shares of Common Stock Outstanding (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail", "shortName": "Stock Transactions and Unit Redemptions - Schedule of Changes in Shares of Common Stock Outstanding (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfCommonStockOutstandingRollForwardTableTextBlock", "us-gaap:StockholdersEquityNoteDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapStatementClassOfStockAxis_us-gaapCommonClassAMember_20190701_20190930", "decimals": "0", "lang": null, "name": "nmrk:ExchangeOrRedemptionForLimitedPartnershipUnit", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R74": { "firstAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "-5", "first": true, "lang": null, "name": "nmrk:ShareRepurchaseAndRedemptionUnitRemainingAuthorizedAmount", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100730 - Disclosure - Stock Transactions and Unit Redemptions - Schedule of Share Repurchase Activity (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail", "shortName": "Stock Transactions and Unit Redemptions - Schedule of Share Repurchase Activity (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:ScheduleOfShareRepurchaseActivityTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapStatementClassOfStockAxis_us-gaapCommonClassAMember_20190701_20190930", "decimals": "INF", "lang": null, "name": "nmrk:StockRepurchaseProgramNumberOfSharesAnnouncedToBeRepurchased", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R75": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181231", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100740 - Disclosure - Stock Transactions and Unit Redemptions - Schedule of Changes in Carrying Amount of Redeemable Partnership Interest (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInCarryingAmountOfRedeemablePartnershipInterestDetail", "shortName": "Stock Transactions and Unit Redemptions - Schedule of Changes in Carrying Amount of Redeemable Partnership Interest (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:RedeemableNoncontrollingInterestTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:TemporaryEquityNetIncome", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R76": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:ProceedsFromSaleAndMaturityOfMarketableSecurities", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100750 - Disclosure - Marketable Securities - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "shortName": "Marketable Securities - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_srtCounterpartyNameAxis_nmrkNasdaqMember_20190101_20190930", "decimals": "INF", "lang": null, "name": "nmrk:MarketableSecuritiesNumberOfSharesSold", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R77": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:IncomeLossFromEquityMethodInvestments", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100760 - Disclosure - Investments - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "shortName": "Investments - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:EquityMethodInvestmentsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapBalanceSheetLocationAxis_us-gaapOtherNoncurrentAssetsMember_20181231", "decimals": "-5", "lang": null, "name": "us-gaap:EquityMethodInvestments", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R78": { "firstAnchor": { "ancestors": [ "span", "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "2", "first": true, "lang": null, "name": "nmrk:PercentageOfLiquidityRequirementOfOutstandingPrincipalOfTargetedAffordableHousingLoansServiced", "reportCount": 1, "unique": true, "unitRef": "U_xbrlipure", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100770 - Disclosure - Capital and Liquidity Requirements - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail", "shortName": "Capital and Liquidity Requirements - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "2", "first": true, "lang": null, "name": "nmrk:PercentageOfLiquidityRequirementOfOutstandingPrincipalOfTargetedAffordableHousingLoansServiced", "reportCount": 1, "unique": true, "unitRef": "U_xbrlipure", "xsiNil": "false" } }, "R79": { "firstAnchor": { "ancestors": [ "p", "us-gaap:FinancingReceivablesTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:MaximumPeriodOfLoansHeldForSaleSold", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100780 - Disclosure - Loans Held for Sale, at Fair Value - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail", "shortName": "Loans Held for Sale, at Fair Value - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:FinancingReceivablesTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:MaximumPeriodOfLoansHeldForSaleSold", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R8": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapStatementEquityComponentsAxis_us-gaapNoncontrollingInterestMember_20180101_20180930", "decimals": "INF", "first": true, "lang": null, "name": "nmrk:NoncontrollingInterestFromSubsidiaryEquityIssuanceShares", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "100070 - Statement - Condensed Consolidated Statements of Changes in Equity (Parenthetical)", "role": "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical", "shortName": "Condensed Consolidated Statements of Changes in Equity (Parenthetical)", "subGroupType": "parenthetical", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapStatementEquityComponentsAxis_us-gaapNoncontrollingInterestMember_20180101_20180930", "decimals": "INF", "first": true, "lang": null, "name": "nmrk:NoncontrollingInterestFromSubsidiaryEquityIssuanceShares", "reportCount": 1, "unique": true, "unitRef": "U_xbrlishares", "xsiNil": "false" } }, "R80": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:LoansHeldForSaleFairValueDisclosure", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100790 - Disclosure - Loans Held for Sale, at Fair Value - Summary of Loans Held for Sale at Cost Basis and Fair Value (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail", "shortName": "Loans Held for Sale, at Fair Value - Summary of Loans Held for Sale at Cost Basis and Fair Value (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "ix:continuation", "us-gaap:FinancingReceivablesTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapFairValueByMeasurementBasisAxis_us-gaapCarryingReportedAmountFairValueDisclosureMember_20190930", "decimals": "-3", "lang": null, "name": "nmrk:LoansHeldForSaleCostBasis", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R81": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock", "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100800 - Disclosure - Derivatives - Fair Value of Derivative Contracts (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "shortName": "Derivatives - Fair Value of Derivative Contracts (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock", "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapFinancialInstrumentAxis_us-gaapInterestRateLockCommitmentsMember_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:DerivativeNotionalAmount", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R82": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock", "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100810 - Disclosure - Derivatives - Fair Value of Derivative Contracts (Parenthetical) (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "shortName": "Derivatives - Fair Value of Derivative Contracts (Parenthetical) (Detail)", "subGroupType": "parenthetical", "uniqueAnchor": { "ancestors": [ "link:footnote", "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock", "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapFinancialInstrumentAxis_us-gaapForwardContractsMember_us-gaapIncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_nmrkNasdaqOmxMember_20181231", "decimals": "-5", "lang": "en-US", "name": "us-gaap:DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R83": { "firstAnchor": { "ancestors": [ "p", "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapFinancialInstrumentAxis_us-gaapInterestRateLockCommitmentsMember_us-gaapIncomeStatementLocationAxis_nmrkCostOfServicesDirectLaborMember_20190701_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:DerivativeGainLossOnDerivativeNet", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100820 - Disclosure - Derivatives - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "shortName": "Derivatives - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": null }, "R84": { "firstAnchor": { "ancestors": [ "p", "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapFinancialInstrumentAxis_us-gaapInterestRateLockCommitmentsMember_us-gaapIncomeStatementLocationAxis_nmrkCostOfServicesDirectLaborMember_20190701_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:DerivativeGainLossOnDerivativeNet", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100830 - Disclosure - Derivatives - Gains and Losses on Derivative Contracts Included on Condensed Consolidated Statements of Operations (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail", "shortName": "Derivatives - Gains and Losses on Derivative Contracts Included on Condensed Consolidated Statements of Operations (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfDerivativeInstrumentsGainLossInStatementOfFinancialPerformanceTextBlock", "us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapHedgingDesignationAxis_us-gaapNondesignatedMember_20190701_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:DerivativeGainLossOnDerivativeNet", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R85": { "firstAnchor": { "ancestors": [ "p", "nmrk:CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:CreditEnhancementAgreementDate", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100840 - Disclosure - Credit Enhancement Receivable, Contingent Liability and Credit Enhancement Deposit - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "shortName": "Credit Enhancement Receivable, Contingent Liability and Credit Enhancement Deposit - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "nmrk:CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "nmrk:CreditEnhancementAgreementDate", "reportCount": 1, "unique": true, "unitRef": null, "xsiNil": "false" } }, "R86": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100850 - Disclosure - Revenues from Contracts with Customers - Schedule of Revenues from Contracts with Customers and Other Sources of Revenues (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "shortName": "Revenues from Contracts with Customers - Schedule of Revenues from Contracts with Customers and Other Sources of Revenues (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:ScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesTableTextBlock", "us-gaap:RevenueFromContractWithCustomerTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "lang": null, "name": "nmrk:ServicingFeesAndOtherRevenue", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R87": { "firstAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:ContractWithCustomerLiabilityNoncurrent", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100860 - Disclosure - Revenues from Contracts with Customers - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersAdditionalInformationDetail", "shortName": "Revenues from Contracts with Customers - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181231", "decimals": "-5", "lang": null, "name": "us-gaap:ContractWithCustomerLiabilityNoncurrent", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R88": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:SummaryOfGainsFromMortgageBankingActivitiesNetTableTextBlock", "nmrk:GainsFromMortgageBankingActivitiesOriginationsNetTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:FeesAndCommissionsMortgageBankingAndServicing", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100870 - Disclosure - Gains From Mortgage Banking Activities/Originations, Net - Summary of Gains From Mortgage Banking Activities/Originations, Net (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetSummaryOfGainsFromMortgageBankingActivitiesOriginationsNetDetail", "shortName": "Gains From Mortgage Banking Activities/Originations, Net - Summary of Gains From Mortgage Banking Activities/Originations, Net (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:SummaryOfGainsFromMortgageBankingActivitiesNetTableTextBlock", "nmrk:GainsFromMortgageBankingActivitiesOriginationsNetTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "lang": null, "name": "nmrk:FairValueOfExpectedNetFutureCashFlowsFromServicingRecognizedAtCommitmentNet", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R89": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfServicingAssetsAtAmortizedValueTextBlock", "nmrk:MortgageServicingRightsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapFairValueByAssetClassAxis_nmrkMortgageServicingRightsMember_20190630", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:ServicingAssetAtAmortizedValue", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100880 - Disclosure - Mortgage Servicing Rights, Net (\"MSRs\") - Summary of Changes in the Carrying Amount of Mortgage Servicing Rights (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail", "shortName": "Mortgage Servicing Rights, Net (\"MSRs\") - Summary of Changes in the Carrying Amount of Mortgage Servicing Rights (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfServicingAssetsAtAmortizedValueTextBlock", "nmrk:MortgageServicingRightsTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_us-gaapFairValueByAssetClassAxis_nmrkMortgageServicingRightsMember_20190630", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:ServicingAssetAtAmortizedValue", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R9": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:ProfitLoss", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "statement", "isDefault": "false", "longName": "100080 - Statement - Condensed Consolidated Statements of Cash Flows", "role": "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows", "shortName": "Condensed Consolidated Statements of Cash Flows", "subGroupType": "", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "-3", "lang": null, "name": "nmrk:GainOnOriginatedMortgageServicingRights", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R90": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:ComponentsOfServicingFeesTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:ContractuallySpecifiedServicingFeesAmount", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100890 - Disclosure - Mortgage Servicing Rights, Net (\"MSRs\") - Components of Servicing Fees Included in \"Management Services, Servicing Fees and Other\" (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail", "shortName": "Mortgage Servicing Rights, Net (\"MSRs\") - Components of Servicing Fees Included in \"Management Services, Servicing Fees and Other\" (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "nmrk:ComponentsOfServicingFeesTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:ContractuallySpecifiedServicingFeesAmount", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R91": { "firstAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-8", "first": true, "lang": null, "name": "nmrk:PrimaryServicingPortfolio", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100900 - Disclosure - Mortgage Servicing Rights, Net (\"MSRs\") - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "shortName": "Mortgage Servicing Rights, Net (\"MSRs\") - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-8", "first": true, "lang": null, "name": "nmrk:PrimaryServicingPortfolio", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R92": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181231", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:Goodwill", "reportCount": 1, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100910 - Disclosure - Goodwill and Other Intangible Assets, Net - Summary of Changes in Carrying Amount of Goodwill (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetSummaryOfChangesInCarryingAmountOfGoodwillDetail", "shortName": "Goodwill and Other Intangible Assets, Net - Summary of Changes in Carrying Amount of Goodwill (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfGoodwillTextBlock", "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": "-3", "lang": null, "name": "us-gaap:GoodwillAcquiredDuringPeriod", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R93": { "firstAnchor": { "ancestors": [ "span", "p", "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181001_20181231", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:GoodwillImpairmentLoss", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100920 - Disclosure - Goodwill and Other Intangible Assets, Net - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetAdditionalInformationDetail", "shortName": "Goodwill and Other Intangible Assets, Net - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "span", "p", "us-gaap:GoodwillAndIntangibleAssetsDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20181001_20181231", "decimals": "INF", "first": true, "lang": null, "name": "us-gaap:GoodwillImpairmentLoss", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R94": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100930 - Disclosure - Goodwill and Other Intangible Assets, Net - Components of Other Intangible Assets (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail", "shortName": "Goodwill and Other Intangible Assets, Net - Components of Other Intangible Assets (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R95": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100940 - Disclosure - Goodwill and Other Intangible Assets, Net - Schedule of Estimated Future Amortization of Definite Life Intangible Assets (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail", "shortName": "Goodwill and Other Intangible Assets, Net - Schedule of Estimated Future Amortization of Definite Life Intangible Assets (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R96": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:PropertyPlantAndEquipmentTextBlock", "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:PropertyPlantAndEquipmentGross", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100950 - Disclosure - Fixed Assets, Net - Components of Fixed Assets, Net (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail", "shortName": "Fixed Assets, Net - Components of Fixed Assets, Net (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:PropertyPlantAndEquipmentTextBlock", "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:PropertyPlantAndEquipmentGross", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R97": { "firstAnchor": { "ancestors": [ "p", "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:Depreciation", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100960 - Disclosure - Fixed Assets, Net - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail", "shortName": "Fixed Assets, Net - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:PropertyPlantAndEquipmentDisclosureTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-5", "first": true, "lang": null, "name": "us-gaap:Depreciation", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R98": { "firstAnchor": { "ancestors": [ "p", "us-gaap:LesseeLeasesPolicyTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190101_20190930", "decimals": null, "first": true, "lang": "en-US", "name": "us-gaap:LesseeOperatingLeaseOptionToExtend", "reportCount": 1, "unitRef": null, "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100970 - Disclosure - Leases - Additional Information (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "shortName": "Leases - Additional Information (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "us-gaap:LesseeOperatingLeasesTextBlock", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190701_20190930", "decimals": "-5", "lang": null, "name": "us-gaap:OperatingLeaseCost", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } }, "R99": { "firstAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" }, "groupType": "disclosure", "isDefault": "false", "longName": "100980 - Disclosure - Leases - Schedule of Future Minimum Rental Payments for Operating Leases under Topic 842 (Detail)", "role": "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail", "shortName": "Leases - Schedule of Future Minimum Rental Payments for Operating Leases under Topic 842 (Detail)", "subGroupType": "details", "uniqueAnchor": { "ancestors": [ "p", "td", "tr", "table", "div", "us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock", "ix:continuation", "body", "html" ], "baseRef": "nmrk-10q_20190930.htm", "contextRef": "C_0001690680_20190930", "decimals": "-3", "first": true, "lang": null, "name": "us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear", "reportCount": 1, "unique": true, "unitRef": "U_iso4217USD", "xsiNil": "false" } } }, "segmentCount": 163, "tag": { "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_CoverAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cover page.", "label": "Cover [Abstract]" } } }, "localname": "CoverAbstract", "nsuri": "http://xbrl.sec.gov/dei/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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "gMonthDayItemType" }, "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "gYearItemType" }, "dei_DocumentInformationLineItems": { "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": "Document Information [Line Items]", "terseLabel": "Document Information [Line Items]" } } }, "localname": "DocumentInformationLineItems", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "stringItemType" }, "dei_DocumentInformationTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Container to support the formal attachment of each official or unofficial, public or private document as part of a submission package.", "label": "Document Information [Table]", "terseLabel": "Document Information [Table]" } } }, "localname": "DocumentInformationTable", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "stringItemType" }, "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "dateItemType" }, "dei_DocumentQuarterlyReport": { "auth_ref": [ "r540" ], "lang": { "en-US": { "role": { "documentation": "Boolean flag that is true only for a form used as an quarterly report.", "label": "Document Quarterly Report", "terseLabel": "Document Quarterly Report" } } }, "localname": "DocumentQuarterlyReport", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_DocumentTransitionReport": { "auth_ref": [ "r541" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_DocumentType": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.", "label": "Document Type", "terseLabel": "Document Type" } } }, "localname": "DocumentType", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "submissionTypeItemType" }, "dei_EntityAddressAddressLine1": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Address Line 1 such as Attn, Building Name, Street Name", "label": "Entity Address Address Line1", "terseLabel": "Entity Address, Address Line One" } } }, "localname": "EntityAddressAddressLine1", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_EntityAddressCityOrTown": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Name of the City or Town", "label": "Entity Address City Or Town", "terseLabel": "Entity Address, City or Town" } } }, "localname": "EntityAddressCityOrTown", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_EntityAddressPostalZipCode": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Code for the postal or zip code", "label": "Entity Address Postal Zip Code", "terseLabel": "Entity Address, Postal Zip Code" } } }, "localname": "EntityAddressPostalZipCode", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_EntityAddressStateOrProvince": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Name of the state or province.", "label": "Entity Address State Or Province", "terseLabel": "Entity Address, State or Province" } } }, "localname": "EntityAddressStateOrProvince", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "stateOrProvinceItemType" }, "dei_EntityCentralIndexKey": { "auth_ref": [ "r542" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "centralIndexKeyItemType" }, "dei_EntityCommonStockSharesOutstanding": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument.", "label": "Entity Common Stock Shares Outstanding", "verboseLabel": "Entity Common Stock, Shares Outstanding" } } }, "localname": "EntityCommonStockSharesOutstanding", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "sharesItemType" }, "dei_EntityCurrentReportingStatus": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Indicate 'Yes' or 'No' whether registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. This information should be based on the registrant's current or most recent filing containing the related disclosure.", "label": "Entity Current Reporting Status", "terseLabel": "Entity Current Reporting Status" } } }, "localname": "EntityCurrentReportingStatus", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "yesNoItemType" }, "dei_EntityDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "All the names of the entities being reported upon in a document. Any legal structure used to conduct activities or to hold assets. Some examples of such structures are corporations, partnerships, limited liability companies, grantor trusts, and other trusts. This item does not include business and geographical segments which are included in the geographical or business segments domains.", "label": "Entity [Domain]", "terseLabel": "Entity" } } }, "localname": "EntityDomain", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "dei_EntityEmergingGrowthCompany": { "auth_ref": [ "r542" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_EntityFileNumber": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.", "label": "Entity File Number", "terseLabel": "Entity File Number" } } }, "localname": "EntityFileNumber", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "fileNumberItemType" }, "dei_EntityFilerCategory": { "auth_ref": [ "r542" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "filerCategoryItemType" }, "dei_EntityIncorporationStateCountryCode": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Two-character EDGAR code representing the state or country of incorporation.", "label": "Entity Incorporation State Country Code", "terseLabel": "Entity Incorporation, State or Country Code" } } }, "localname": "EntityIncorporationStateCountryCode", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "edgarStateCountryItemType" }, "dei_EntityInteractiveDataCurrent": { "auth_ref": [ "r543" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "yesNoItemType" }, "dei_EntityRegistrantName": { "auth_ref": [ "r542" ], "lang": { "en-US": { "role": { "documentation": "The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.", "label": "Entity Registrant Name", "verboseLabel": "Entity Registrant Name" } } }, "localname": "EntityRegistrantName", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_EntityShellCompany": { "auth_ref": [ "r542" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_EntitySmallBusiness": { "auth_ref": [ "r542" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "booleanItemType" }, "dei_EntityTaxIdentificationNumber": { "auth_ref": [ "r542" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "employerIdItemType" }, "dei_LegalEntityAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The set of legal entities associated with a report.", "label": "Legal Entity [Axis]", "terseLabel": "Legal Entity" } } }, "localname": "LegalEntityAxis", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "normalizedStringItemType" }, "dei_Security12bTitle": { "auth_ref": [ "r538" ], "lang": { "en-US": { "role": { "documentation": "Title of a 12(b) registered security.", "label": "Security12b Title", "terseLabel": "Title of 12(b) Security" } } }, "localname": "Security12bTitle", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "securityTitleItemType" }, "dei_SecurityExchangeName": { "auth_ref": [ "r539" ], "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.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "edgarExchangeCodeItemType" }, "dei_TradingSymbol": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Trading symbol of an instrument as listed on an exchange.", "label": "Trading Symbol", "terseLabel": "Trading Symbol" } } }, "localname": "TradingSymbol", "nsuri": "http://xbrl.sec.gov/dei/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation" ], "xbrltype": "tradingSymbolItemType" }, "nmrk_ACRESMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "ACRES.", "label": "A C R E S [Member]", "terseLabel": "ACRES [Member]" } } }, "localname": "ACRESMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_AccountsPayableAccruedAndOtherLiabilitiesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Accounts Payable Accrued and Other Liabilities [Member]", "label": "Accounts Payable Accrued And Other Liabilities [Member]", "terseLabel": "RBC [Member]" } } }, "localname": "AccountsPayableAccruedAndOtherLiabilitiesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_AccountsPayableAccruedExpensesAndOtherLiabilitiesCurrentAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Accounts payable, accrued expenses and other liabilities, current.", "label": "Accounts Payable Accrued Expenses And Other Liabilities Current [Abstract]" } } }, "localname": "AccountsPayableAccruedExpensesAndOtherLiabilitiesCurrentAbstract", "nsuri": "http://www.ngkf.com/20190930", "xbrltype": "stringItemType" }, "nmrk_AccountsPayableAccruedExpensesAndOtherLiabilitiesCurrentAndNoncurrentAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Accounts payable, accrued expenses and other liabilities, current and noncurrent.", "label": "Accounts Payable Accrued Expenses And Other Liabilities Current And Noncurrent [Abstract]" } } }, "localname": "AccountsPayableAccruedExpensesAndOtherLiabilitiesCurrentAndNoncurrentAbstract", "nsuri": "http://www.ngkf.com/20190930", "xbrltype": "stringItemType" }, "nmrk_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for accounts payable, accrued liabilities and other liabilities disclosure, current and noncurrent.", "label": "Accounts Payable Accrued Liabilities And Other Liabilities Disclosure Current And Noncurrent [Text Block]", "terseLabel": "Accounts Payable, Accrued Expenses and Other Liabilities" } } }, "localname": "AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentAndNoncurrentTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilities" ], "xbrltype": "textBlockItemType" }, "nmrk_AccountsPayableAndAccruedExpensesCurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": 10010.0, "parentTag": "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Accounts payable and accrued expenses, current.", "label": "Accounts Payable And Accrued Expenses Current", "terseLabel": "Accounts payable and accrued expenses" } } }, "localname": "AccountsPayableAndAccruedExpensesCurrent", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_AccruedCompensationNoncurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail": { "order": 10030.0, "parentTag": "us-gaap_OtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Accrued compensation, noncurrent.", "label": "Accrued Compensation Noncurrent", "terseLabel": "Accrued compensation" } } }, "localname": "AccruedCompensationNoncurrent", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_AccruedPayrollTaxesNoncurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail": { "order": 10020.0, "parentTag": "us-gaap_OtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Accrued payroll taxes noncurrent.", "label": "Accrued Payroll Taxes Noncurrent", "terseLabel": "Payroll taxes payable" } } }, "localname": "AccruedPayrollTaxesNoncurrent", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_AcquisitionsFromTwoThousandFourteenThroughTwoThousandNineteenMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Acquisitions from 2014 through 2019.", "label": "Acquisitions From Two Thousand Fourteen Through Two Thousand Nineteen [Member]", "terseLabel": "Acquisitions from 2014 through 2019 [Member]" } } }, "localname": "AcquisitionsFromTwoThousandFourteenThroughTwoThousandNineteenMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_AllocationOfIncomeLossToLimitedPartnershipInterestDiluted": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail": { "order": 10060.0, "parentTag": "us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Allocation of income loss to limited partnership interest diluted.", "label": "Allocation Of Income Loss To Limited Partnership Interest Diluted", "terseLabel": "Allocations of net income to limited partnership interests in Newmark Holdings, net of tax" } } }, "localname": "AllocationOfIncomeLossToLimitedPartnershipInterestDiluted", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_BGCHoldingsLimitedPartnershipMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "BGC Holdings Limited Partnership.", "label": "B G C Holdings Limited Partnership [Member]", "terseLabel": "BGC Holdings, L.P. [Member]", "verboseLabel": "BGC Holdings, L.P. [Member]" } } }, "localname": "BGCHoldingsLimitedPartnershipMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_BGCPartnersIncMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "BGC Partners Inc.", "label": "B G C Partners Inc [Member]", "terseLabel": "BGC Partners Inc [Member]" } } }, "localname": "BGCPartnersIncMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_BGCPartnersLPAndItsOperatingSubsidiariesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "BGC Partners, L.P and its Operating Subsidiaries.", "label": "B G C Partners L P And Its Operating Subsidiaries [Member]", "terseLabel": "BGC Partners, L.P. and its Operating Subsidiaries [Member]" } } }, "localname": "BGCPartnersLPAndItsOperatingSubsidiariesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_BelowMarketLeasesAcquiredWeightedAverageUsefulLife": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Below market leases acquired weighted average useful life.", "label": "Below Market Leases Acquired Weighted Average Useful Life", "terseLabel": "Below market leases, Weighted-Average Remaining Life (Years)" } } }, "localname": "BelowMarketLeasesAcquiredWeightedAverageUsefulLife", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "durationItemType" }, "nmrk_BerkeleyPointFinancialLLCMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Berkeley Point Financial LLC.", "label": "Berkeley Point Financial L L C [Member]", "terseLabel": "BPF [Member]" } } }, "localname": "BerkeleyPointFinancialLLCMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_BostonAndPittsburghMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Boston and Pittsburgh.", "label": "Boston And Pittsburgh [Member]", "terseLabel": "Boston and Pittsburg Acquisitions [Member]" } } }, "localname": "BostonAndPittsburghMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_BusinessAcquisitionCombinationContingentConsiderationEquityInterestsIssuableNumberOfShares": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Business acquisition combination contingent consideration equity interests issuable number of shares.", "label": "Business Acquisition Combination Contingent Consideration Equity Interests Issuable Number Of Shares", "positiveLabel": "Business acquisition, contingent consideration limited partnership units" } } }, "localname": "BusinessAcquisitionCombinationContingentConsiderationEquityInterestsIssuableNumberOfShares", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedCompensation": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10050.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Business combination recognized identifiable assets acquired and liabilities assumed current liabilities accrued compensation.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Accrued Compensation", "terseLabel": "Accrued compensation" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedCompensation", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAssets": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10110.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Business combination recognized identifiable assets acquired and liabilities assumed other assets.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Other Assets", "terseLabel": "Other assets" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAssets", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_CFRealEstateFinanceHoldingsLimitedPartnershipMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "CF Real Estate Finance Holdings, L.P.", "label": "C F Real Estate Finance Holdings Limited Partnership [Member]", "terseLabel": "CF Real Estate Finance Holdings, L.P. [Member]" } } }, "localname": "CFRealEstateFinanceHoldingsLimitedPartnershipMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CaliforniaAndTexasMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "California and Texas.", "label": "California And Texas [Member]", "terseLabel": "California and Texas [Member]" } } }, "localname": "CaliforniaAndTexasMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CantorAndCFGMMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cantor and CFGM.", "label": "Cantor And C F G M [Member]", "terseLabel": "Cantor And CFGM [Member]" } } }, "localname": "CantorAndCFGMMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CantorCommercialRealEstateCompanyMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cantor Commercial Real Estate Company [Member]", "label": "Cantor Commercial Real Estate Company [Member]", "terseLabel": "CCRE [Member]" } } }, "localname": "CantorCommercialRealEstateCompanyMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CantorCreditAgreementMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Cantor Credit Agreement [Member]", "terseLabel": "Cantor Credit Agreement [Member]" } } }, "localname": "CantorCreditAgreementMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CantorFitzgeraldCoMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cantor Fitzgerald Co.", "label": "Cantor Fitzgerald Co [Member]", "terseLabel": "CF & Co [Member]" } } }, "localname": "CantorFitzgeraldCoMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CantorFitzgeraldLimitedPartnershipAndBGCPartnersIncorporationMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cantor Fitzgerald, L.P. and BGC Partners, Inc.", "label": "Cantor Fitzgerald Limited Partnership And B G C Partners Incorporation [Member]", "terseLabel": "Cantor and BGC [Member]" } } }, "localname": "CantorFitzgeraldLimitedPartnershipAndBGCPartnersIncorporationMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CantorFitzgeraldLimitedPartnershipAndItsAffiliatesOtherThanBGCPartnersIncorporationMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cantor Fitzgerald, L.P. and its affiliates other than BGC Partners, Inc.", "label": "Cantor Fitzgerald Limited Partnership And Its Affiliates Other Than B G C Partners Incorporation [Member]", "terseLabel": "Cantor and its Affiliates (Other Than BGC) [Member]" } } }, "localname": "CantorFitzgeraldLimitedPartnershipAndItsAffiliatesOtherThanBGCPartnersIncorporationMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CantorMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cantor.", "label": "Cantor [Member]", "terseLabel": "Cantor [Member]" } } }, "localname": "CantorMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CantorRightsToPurchaseExchangeableUnitsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cantor Rights To Purchase Exchangeable Units [Member]", "label": "Cantor Rights To Purchase Exchangeable Units [Member]", "terseLabel": "Cantor Rights to Purchase Exchangeable Units [Member]" } } }, "localname": "CantorRightsToPurchaseExchangeableUnitsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CapitalMarketsCommissionsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Capital markets commissions.", "label": "Capital Markets Commissions [Member]", "terseLabel": "Capital Markets Commissions [Member]" } } }, "localname": "CapitalMarketsCommissionsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail" ], "xbrltype": "domainItemType" }, "nmrk_CashPaidDuringPeriodForAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cash paid during period for.", "label": "Cash Paid During Period For [Abstract]", "terseLabel": "Cash paid during the period for:" } } }, "localname": "CashPaidDuringPeriodForAbstract", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "stringItemType" }, "nmrk_CertainAssetsOfESpeedIncorporationMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Certain assets of eSpeed incorporation.", "label": "Certain Assets Of E Speed Incorporation [Member]", "verboseLabel": "Certain Assets of Nasdaq [Member]" } } }, "localname": "CertainAssetsOfESpeedIncorporationMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CfManagementGroupIncMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "CF Group Management Inc. [Member]", "label": "Cf Management Group Inc [Member]", "terseLabel": "CF Group Management, Inc. [Member]" } } }, "localname": "CfManagementGroupIncMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ClassOfCommonStockExchangedToAnotherClassOfCommonStock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Class Of Common Stock Exchanged To Another Class Of Common Stock", "label": "Class Of Common Stock Exchanged To Another Class Of Common Stock", "terseLabel": "Number of shares, right to exchange from Class A to Class A or Class B common stock" } } }, "localname": "ClassOfCommonStockExchangedToAnotherClassOfCommonStock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_CommittedLinesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Committed lines.", "label": "Committed Lines [Member]", "terseLabel": "Committed Lines [Member]" } } }, "localname": "CommittedLinesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "domainItemType" }, "nmrk_CommonClassAOrClassBMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Common Class A or Class B.", "label": "Common Class A Or Class B [Member]", "terseLabel": "Class A or Class B Common Stock [Member]" } } }, "localname": "CommonClassAOrClassBMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CompensationAndEmployeeBenefitsNet": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10100.0, "parentTag": "us-gaap_CostsAndExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The aggregate amount of expenditures for salaries, wages, profit sharing and incentives compensation, and other employee benefits, including share-based compensation and the expense related to allocation of income to limited partnership units and founding/working partner units.", "label": "Compensation And Employee Benefits Net", "terseLabel": "Compensation and employee benefits", "totalLabel": "Total compensation and employee benefits" } } }, "localname": "CompensationAndEmployeeBenefitsNet", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "nmrk_ComponentsOfServicingFeesTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Components of servicing fees.", "label": "Components Of Servicing Fees Table [Text Block]", "terseLabel": "Components of Servicing Fees Included in \"Management Services, Servicing Fees and Other\"" } } }, "localname": "ComponentsOfServicingFeesTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsTables" ], "xbrltype": "textBlockItemType" }, "nmrk_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposureWithoutCreditProtection": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Concentration risk credit risk financial instrument maximum exposure without credit protection.", "label": "Concentration Risk Credit Risk Financial Instrument Maximum Exposure Without Credit Protection", "terseLabel": "Maximum loss exposure without any form of credit protection" } } }, "localname": "ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposureWithoutCreditProtection", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ContingentClassACommonStockMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Contingent class A common stock.", "label": "Contingent Class A Common Stock [Member]", "terseLabel": "Contingent Class A Common Stock" } } }, "localname": "ContingentClassACommonStockMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "domainItemType" }, "nmrk_ContingentConsiderationLiabilityFairValueDisclosure": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail": { "order": 10010.0, "parentTag": "us-gaap_LiabilitiesFairValueDisclosure", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Contingent Consideration Liability Fair Value Disclosure", "label": "Contingent Consideration Liability Fair Value Disclosure", "terseLabel": "Accounts payable, accrued expenses and other liabilities\u2014contingent consideration" } } }, "localname": "ContingentConsiderationLiabilityFairValueDisclosure", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ContingentConsiderationLiabilityMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Contingent Consideration Liability [Member]", "label": "Contingent Consideration Liability [Member]", "terseLabel": "Contingent Consideration [Member]" } } }, "localname": "ContingentConsiderationLiabilityMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "nmrk_ContingentPaymentDueDate": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Contingent payment due date.", "label": "Contingent Payment Due Date", "terseLabel": "Contingent payment due date" } } }, "localname": "ContingentPaymentDueDate", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "nmrk_ContingentPaymentsDescription": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Contingent payments description.", "label": "Contingent Payments Description", "terseLabel": "Contingent payments description" } } }, "localname": "ContingentPaymentsDescription", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_ContractuallySpecifiedServicingFeesAncillaryFeesEscrowInterestAndPlacementFeesEarnedInExchangeForServicingFinancialAssets": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Contractually specified servicing fees, ancillary fees, escrow interest and placement fees earned in exchange for servicing financial assets.", "label": "Contractually Specified Servicing Fees Ancillary Fees Escrow Interest And Placement Fees Earned In Exchange For Servicing Financial Assets", "totalLabel": "Total" } } }, "localname": "ContractuallySpecifiedServicingFeesAncillaryFeesEscrowInterestAndPlacementFeesEarnedInExchangeForServicingFinancialAssets", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ConversionOfCommonStock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Conversion of common stock.", "label": "Conversion Of Common Stock", "terseLabel": "Conversion of common stock" } } }, "localname": "ConversionOfCommonStock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails" ], "xbrltype": "integerItemType" }, "nmrk_ConvertedTermLoanMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Converted term loan.", "label": "Converted Term Loan [Member]", "terseLabel": "Converted Term Loan [Member]" } } }, "localname": "ConvertedTermLoanMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CostOfServicesDirectLaborMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Cost of services direct labor.", "label": "Cost Of Services Direct Labor [Member]", "terseLabel": "Compensation and Employee Benefits [Member]" } } }, "localname": "CostOfServicesDirectLaborMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "domainItemType" }, "nmrk_CreditEnhancementAgreementDate": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Credit enhancement agreement date.", "label": "Credit Enhancement Agreement Date", "terseLabel": "Credit enhancement agreement date" } } }, "localname": "CreditEnhancementAgreementDate", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "nmrk_CreditEnhancementAgreementMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Credit Enhancement Agreement.", "label": "Credit Enhancement Agreement [Member]", "terseLabel": "Credit Enhancement Agreement [Member]" } } }, "localname": "CreditEnhancementAgreementMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_CreditEnhancementReceivable": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Credit enhancement receivable.", "label": "Credit Enhancement Receivable", "terseLabel": "Credit enhancement receivable" } } }, "localname": "CreditEnhancementReceivable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Credit enhancement receivable contingent liability and credit enhancement deposit.", "label": "Credit Enhancement Receivable Contingent Liability And Credit Enhancement Deposit [Abstract]" } } }, "localname": "CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAbstract", "nsuri": "http://www.ngkf.com/20190930", "xbrltype": "stringItemType" }, "nmrk_CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Credit enhancement receivable contingent liability and credit enhancement deposit.", "label": "Credit Enhancement Receivable Contingent Liability And Credit Enhancement Deposit [Line Items]", "terseLabel": "Credit Enhancement Receivable Contingent Liability And Credit Enhancement Deposit [Line Items]" } } }, "localname": "CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositLineItems", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Credit enhancement receivable contingent liability and credit enhancement deposit.", "label": "Credit Enhancement Receivable Contingent Liability And Credit Enhancement Deposit [Table]", "terseLabel": "Credit Enhancement Receivable Contingent Liability And Credit Enhancement Deposit [Table]" } } }, "localname": "CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Credit enhancement receivable contingent liability and credit enhancement deposit.", "label": "Credit Enhancement Receivable Contingent Liability And Credit Enhancement Deposit [Text Block]", "terseLabel": "Credit Enhancement Receivable, Contingent Liability And Credit Enhancement Deposit" } } }, "localname": "CreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDeposit" ], "xbrltype": "textBlockItemType" }, "nmrk_CumulativeEffectOfRevenueStandardAdoption": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Cumulative effect of revenue standard adoption.", "label": "Cumulative Effect Of Revenue Standard Adoption", "terseLabel": "Cumulative effect of revenue standard adoption" } } }, "localname": "CumulativeEffectOfRevenueStandardAdoption", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "nmrk_DBCaymanMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "DB Cayman.", "label": "D B Cayman [Member]", "terseLabel": "DB Cayman [Member]" } } }, "localname": "DBCaymanMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_DecreaseIncreaseToCreditEnhancementAsset": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail": { "order": 10020.0, "parentTag": "nmrk_ProvisionForRiskSharingObligations", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Decrease increase to credit enhancement asset.", "label": "Decrease Increase To Credit Enhancement Asset", "terseLabel": "Decrease (increase) to credit enhancement asset" } } }, "localname": "DecreaseIncreaseToCreditEnhancementAsset", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_DenverAndPasadenaMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Denver and Pasadena.", "label": "Denver And Pasadena [Member]", "terseLabel": "Denver and Pasadena Acquisitions [Member]" } } }, "localname": "DenverAndPasadenaMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_DescriptionOfBusinessLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Description Of Business [Line Items]", "label": "Description Of Business [Line Items]", "terseLabel": "Description Of Business [Line Items]" } } }, "localname": "DescriptionOfBusinessLineItems", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_DescriptionOfBusinessTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Description Of Business [Table]", "label": "Description Of Business [Table]", "terseLabel": "Description Of Business [Table]" } } }, "localname": "DescriptionOfBusinessTable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_DeterminationPrice": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Determination price.", "label": "Determination Price", "terseLabel": "Determination price" } } }, "localname": "DeterminationPrice", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "perShareItemType" }, "nmrk_DiscountRateOneMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Discount rate one.", "label": "Discount Rate One [Member]", "terseLabel": "Discount Rate One [Member]" } } }, "localname": "DiscountRateOneMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_DiscountRateTwoMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Discount rate two.", "label": "Discount Rate Two [Member]", "terseLabel": "Discount Rate Two [Member]" } } }, "localname": "DiscountRateTwoMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_EarnOutSharesReceivableUnderCommonStockTransaction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Earn out shares receivable under common stock transaction.", "label": "Earn Out Shares Receivable Under Common Stock Transaction", "terseLabel": "Earn-out shares receivable under common stock transaction" } } }, "localname": "EarnOutSharesReceivableUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_EarnOutSharesReceivedUnderCommonStockTransaction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Earn out shares received under common stock transaction.", "label": "Earn Out Shares Received Under Common Stock Transaction", "terseLabel": "Amount recognized in connection with the earn-out including other income (loss)" } } }, "localname": "EarnOutSharesReceivedUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_EconomicInterestOwnershipPercentage": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Economic interest ownership percentage.", "label": "Economic Interest Ownership Percentage", "terseLabel": "Economic interest ownership percentage" } } }, "localname": "EconomicInterestOwnershipPercentage", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_EmployeeLoansMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Employee Loans [Member]", "label": "Employee Loans [Member]", "terseLabel": "Employee Loans [Member]" } } }, "localname": "EmployeeLoansMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_EmployeesAndDirectorsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Employees and directors.", "label": "Employees And Directors [Member]", "terseLabel": "Employees and Directors [Member]" } } }, "localname": "EmployeesAndDirectorsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_EquityBasedCompensationAndAllocationOfNetIncomeToLimitedPartnershipUnitsAndFPUs": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10370.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Equity based compensation and allocation of net income to limited partnership units and FPUs.", "label": "Equity Based Compensation And Allocation Of Net Income To Limited Partnership Units And F P Us", "terseLabel": "Equity-based compensation and allocations of net income to limited partnership units and FPUs" } } }, "localname": "EquityBasedCompensationAndAllocationOfNetIncomeToLimitedPartnershipUnitsAndFPUs", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "nmrk_EquityBasedCompensationAndAllocationsOfNetIncomeToLimitedPartnershipUnits": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10150.0, "parentTag": "nmrk_CompensationAndEmployeeBenefitsNet", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Equity based compensation and allocations of net income to limited partnership units.", "label": "Equity Based Compensation And Allocations Of Net Income To Limited Partnership Units", "terseLabel": "Equity-based compensation and allocations of net income to limited partnership units and FPUs" } } }, "localname": "EquityBasedCompensationAndAllocationsOfNetIncomeToLimitedPartnershipUnits", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "nmrk_EquityLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Equity [Line Items]", "label": "Equity [Line Items]", "terseLabel": "Equity [Line Items]" } } }, "localname": "EquityLineItems", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_EquityTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Equity [Table]", "label": "Equity [Table]", "terseLabel": "Equity [Table]" } } }, "localname": "EquityTable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_EscrowAndCustodialFundsTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Escrow and custodial funds.", "label": "Escrow And Custodial Funds [Text Block]", "terseLabel": "Escrow and Custodial Funds" } } }, "localname": "EscrowAndCustodialFundsTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEscrowAndCustodialFunds" ], "xbrltype": "textBlockItemType" }, "nmrk_EscrowInterestAndPlacementFeesAmount": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail": { "order": 10020.0, "parentTag": "nmrk_ContractuallySpecifiedServicingFeesAncillaryFeesEscrowInterestAndPlacementFeesEarnedInExchangeForServicingFinancialAssets", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Escrow interest and placement fees amount.", "label": "Escrow Interest And Placement Fees Amount", "terseLabel": "Escrow interest and placement fees" } } }, "localname": "EscrowInterestAndPlacementFeesAmount", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_EstimatedFairValueOfLimitedPartnershipUnits": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Estimated fair value of limited partnership units held by executives and non-executive employees, awarded in lieu of cash compensation for salaries, commissions and/or discretionary or guaranteed bonuses.", "label": "Estimated Fair Value Of Limited Partnership Units", "terseLabel": "Aggregate estimated fair value of limited partnership units" } } }, "localname": "EstimatedFairValueOfLimitedPartnershipUnits", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_EstimatedGrantDateFairValueOfOutstandingRsu": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Estimated grant date fair value of outstanding RSU.", "label": "Estimated Grant Date Fair Value Of Outstanding Rsu", "terseLabel": "Aggregate estimated grant date fair value of outstanding RSUs" } } }, "localname": "EstimatedGrantDateFairValueOfOutstandingRsu", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ExchangeOrRedemptionForLimitedPartnershipUnit": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Exchange or redemption for limited partnership unit.", "label": "Exchange Or Redemption For Limited Partnership Unit", "terseLabel": "Limited partnership unit redemption/exchange" } } }, "localname": "ExchangeOrRedemptionForLimitedPartnershipUnit", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail" ], "xbrltype": "sharesItemType" }, "nmrk_ExchangeSharePrice": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Exchange share price.", "label": "Exchange Share Price", "terseLabel": "Exchange share price" } } }, "localname": "ExchangeSharePrice", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "perShareItemType" }, "nmrk_ExchangeabilityGrantedNumberOfUnits": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of limited partnership units granted exchangeability into the company's class A common stock during the period.", "label": "Exchangeability Granted Number Of Units", "terseLabel": "Number of limited partnership units granted exchangeability" } } }, "localname": "ExchangeabilityGrantedNumberOfUnits", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_ExchangeablePreferredLimitedPartnershipUnits": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Exchangeable preferred limited partnership units.", "label": "Exchangeable Preferred Limited Partnership Units", "terseLabel": "Exchangeable preferred limited partnership units" } } }, "localname": "ExchangeablePreferredLimitedPartnershipUnits", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ExchangeablePreferredLimitedPartnershipUnitsIssued": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Exchangeable preferred limited partnership units issued.", "label": "Exchangeable Preferred Limited Partnership Units Issued", "terseLabel": "Exchangeable preferred limited partnership units issued" } } }, "localname": "ExchangeablePreferredLimitedPartnershipUnitsIssued", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ExecutiveOfficerFourMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Executive officer four.", "label": "Executive Officer Four [Member]", "terseLabel": "Mr. Merkel [Member]" } } }, "localname": "ExecutiveOfficerFourMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ExecutiveOfficerOneMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Executive Officer One [Member].", "label": "Executive Officer One [Member]", "terseLabel": "Mr. Lutnick [Member]" } } }, "localname": "ExecutiveOfficerOneMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ExecutiveOfficerThreeMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Executive Officer Three [Member]", "label": "Executive Officer Three [Member]", "terseLabel": "Mr. Rispoli [Member]" } } }, "localname": "ExecutiveOfficerThreeMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ExecutiveOfficerTwoMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Executive Officer Two [Member].", "label": "Executive Officer Two [Member]", "terseLabel": "Mr. Gosin [Member]" } } }, "localname": "ExecutiveOfficerTwoMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ExecutivesAndNonExecutivesEmployeesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Executives and non executives employees.", "label": "Executives And Non Executives Employees [Member]", "terseLabel": "Executives And Non-Executives Employees [Member]" } } }, "localname": "ExecutivesAndNonExecutivesEmployeesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ExpectedPaymentOfSharesUnderCommonStockTransaction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Expected payment of shares under common stock transaction.", "label": "Expected Payment Of Shares Under Common Stock Transaction", "terseLabel": "Expected payment of shares under common stock transaction" } } }, "localname": "ExpectedPaymentOfSharesUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Fair value assets and liabilities measured on recurring basis unobservable input reconciliation.", "label": "Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation Table [Text Block]", "terseLabel": "Changes in Level 3 Nasdaq Forwards, Rate Lock Commitments, Forwards and Contingent Consideration Measured at Fair Value on Recurring Basis" } } }, "localname": "FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesTables" ], "xbrltype": "textBlockItemType" }, "nmrk_FairValueOfCommonStockExpectsToReceive": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value of common stock expects to receive.", "label": "Fair Value Of Common Stock Expects To Receive", "terseLabel": "Fair value of common stock expects to receive" } } }, "localname": "FairValueOfCommonStockExpectsToReceive", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_FairValueOfExpectedNetFutureCashFlowsFromServicingRecognizedAtCommitmentNet": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetSummaryOfGainsFromMortgageBankingActivitiesOriginationsNetDetail": { "order": 10020.0, "parentTag": "us-gaap_GainLossOnSaleOfMortgageLoans", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value of expected net future cash flows from servicing recognized at commitment, net.", "label": "Fair Value Of Expected Net Future Cash Flows From Servicing Recognized At Commitment Net", "terseLabel": "Fair value of expected net future cash flows from servicing recognized at commitment, net" } } }, "localname": "FairValueOfExpectedNetFutureCashFlowsFromServicingRecognizedAtCommitmentNet", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetSummaryOfGainsFromMortgageBankingActivitiesOriginationsNetDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_FannieMaeAndFreddieMacMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Fannie Mae and Freddie Mac.", "label": "Fannie Mae And Freddie Mac [Member]", "terseLabel": "Fannie Mae and Freddie Mac [Member]" } } }, "localname": "FannieMaeAndFreddieMacMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_FannieMaeDUSAndFreddieMacTAHLoansMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Fannie Mae DUS and Freddie Mac TAH loans.", "label": "Fannie Mae D U S And Freddie Mac T A H Loans [Member]", "terseLabel": "Fannie Mae DUS and Freddie Mac TAH Loans [Member]" } } }, "localname": "FannieMaeDUSAndFreddieMacTAHLoansMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_FannieMaeDUSOrFreddieTargetedAffordableHousingLoansMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Fannie Mae DUS or Freddie targeted affordable housing loans.", "label": "Fannie Mae D U S Or Freddie Targeted Affordable Housing Loans [Member]", "terseLabel": "Fannie Mae DUS or Freddie TAH Loans [Member]" } } }, "localname": "FannieMaeDUSOrFreddieTargetedAffordableHousingLoansMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_FannieMaeMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Fannie Mae.", "label": "Fannie Mae [Member]", "terseLabel": "Fannie Mae [Member]" } } }, "localname": "FannieMaeMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_FannieMaeRepurchaseAgreementOpenMaturityMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Fannie Mae repurchase agreement, open maturity.", "label": "Fannie Mae Repurchase Agreement Open Maturity [Member]", "terseLabel": "Fannie Mae Repurchase Agreement, Open Maturity [Member]" } } }, "localname": "FannieMaeRepurchaseAgreementOpenMaturityMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "domainItemType" }, "nmrk_FederalFundRateMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Federal fund rate.", "label": "Federal Fund Rate [Member]", "terseLabel": "Federal Fund Rate [Member]" } } }, "localname": "FederalFundRateMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_FiniteLivedIntangibleAssetsExpectedAmortizationExpense": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Total amount of future amortization expense expected to be recognized following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.", "label": "Finite Lived Intangible Assets Expected Amortization Expense", "totalLabel": "Total" } } }, "localname": "FiniteLivedIntangibleAssetsExpectedAmortizationExpense", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ForwardSaleContractsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Forward sale contracts.", "label": "Forward Sale Contracts [Member]", "terseLabel": "Forward Sale Contracts [Member]" } } }, "localname": "ForwardSaleContractsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "nmrk_GainLossFromMortgageBankingActivitiesNetMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gain (loss) from mortgage banking activities net.", "label": "Gain Loss From Mortgage Banking Activities Net [Member]", "terseLabel": "Gains (Loss) from Mortgage Banking Activities, Net [Member]" } } }, "localname": "GainLossFromMortgageBankingActivitiesNetMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_GainOnOriginatedMortgageServicingRights": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10340.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Gain on originated mortgage servicing rights.", "label": "Gain On Originated Mortgage Servicing Rights", "negatedLabel": "Gain on originated mortgage servicing rights" } } }, "localname": "GainOnOriginatedMortgageServicingRights", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "nmrk_GainRecognizedOnEarnOutReceivableUnderCommonStockTransaction": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Gain recognized on earn-out receivable under common stock transaction.", "label": "Gain Recognized On Earn Out Receivable Under Common Stock Transaction", "terseLabel": "Gain on earn-out, common stock transaction" } } }, "localname": "GainRecognizedOnEarnOutReceivableUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_GainsFromMortgageBankingActivitiesOriginationsNetMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Gains from mortgage banking activities/originations, net.", "label": "Gains From Mortgage Banking Activities Originations Net [Member]", "terseLabel": "Gains From Mortgage Banking Activities/Originations, Net [Member]" } } }, "localname": "GainsFromMortgageBankingActivitiesOriginationsNetMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "domainItemType" }, "nmrk_GainsFromMortgageBankingActivitiesOriginationsNetTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for gain from mortgage banking activities/originations, net.", "label": "Gains From Mortgage Banking Activities Originations Net [Text Block]", "terseLabel": "Gains From Mortgage Banking Activities Originations Net" } } }, "localname": "GainsFromMortgageBankingActivitiesOriginationsNetTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNet" ], "xbrltype": "textBlockItemType" }, "nmrk_GainsLossesRecognizedForFairValueAdjustmentsOnLoansHeldForSale": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Gains (losses) recognized for fair value adjustments on loans held for sale.", "label": "Gains Losses Recognized For Fair Value Adjustments On Loans Held For Sale", "terseLabel": "Gains/(losses) recognized for fair value adjustments on loans held for sale" } } }, "localname": "GainsLossesRecognizedForFairValueAdjustmentsOnLoansHeldForSale", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_GovernmentSponsoredEnterpriseLoansMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Government sponsored enterprise loans.", "label": "Government Sponsored Enterprise Loans [Member]", "terseLabel": "GSE Loans [Member]" } } }, "localname": "GovernmentSponsoredEnterpriseLoansMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_GrantOfExchangeabilityRedemptionAndIssuanceOfLimitedPartnershipInterestsAndIssuanceOfCommonStockShares": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Grant of exchangeability, redemption and issuance of limited partnership interests and issuance of common stock, shares.", "label": "Grant Of Exchangeability Redemption And Issuance Of Limited Partnership Interests And Issuance Of Common Stock Shares", "positiveLabel": "Grant of exchangeability, redemption and issuance of limited partnership interests and issuance of common stock, shares" } } }, "localname": "GrantOfExchangeabilityRedemptionAndIssuanceOfLimitedPartnershipInterestsAndIssuanceOfCommonStockShares", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "sharesItemType" }, "nmrk_GrossRevenueOnEarnOutSharesReceivablePerYearUnderCommonStockTransaction": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Gross revenue on earn out shares receivable per year under common stock transaction.", "label": "Gross Revenue On Earn Out Shares Receivable Per Year Under Common Stock Transaction", "terseLabel": "Gross revenue on earn-out receivable per year under common stock transaction" } } }, "localname": "GrossRevenueOnEarnOutSharesReceivablePerYearUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_GrossRevenueOnExpectedPaymentPerYearUnderCommonStockTransaction": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Gross revenue on expected payment per year under common stock transaction.", "label": "Gross Revenue On Expected Payment Per Year Under Common Stock Transaction", "terseLabel": "Gross revenue on expected payment per year under common stock transaction." } } }, "localname": "GrossRevenueOnExpectedPaymentPerYearUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_GuarantyLiabilitiesIncreaseToProvision": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Guaranty liabilities increase to provision.", "label": "Guaranty Liabilities Increase To Provision", "negatedLabel": "Increase to provision" } } }, "localname": "GuarantyLiabilitiesIncreaseToProvision", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfChangesInEstimatedLiabilityUnderGuaranteeLiabilityDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_GuarantyLiabilitiesReversalToProvision": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Guaranty liabilities, reversal to provision.", "label": "Guaranty Liabilities Reversal To Provision", "terseLabel": "Reversal of provision" } } }, "localname": "GuarantyLiabilitiesReversalToProvision", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfChangesInEstimatedLiabilityUnderGuaranteeLiabilityDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_IncreaseDecreaseToContingentLiability": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail": { "order": 10030.0, "parentTag": "nmrk_ProvisionForRiskSharingObligations", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Increase Decrease to Contingent Liability.", "label": "Increase Decrease To Contingent Liability", "terseLabel": "Increase (decrease) to contingent liability" } } }, "localname": "IncreaseDecreaseToContingentLiability", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_IncreaseDecreaseToFinancialGuaranteeLiability": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail": { "order": 10010.0, "parentTag": "nmrk_ProvisionForRiskSharingObligations", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Increase decrease to financial guarantee liability.", "label": "Increase Decrease To Financial Guarantee Liability", "terseLabel": "Increase (decrease) to financial guarantee liability" } } }, "localname": "IncreaseDecreaseToFinancialGuaranteeLiability", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_IncrementalCommonSharesAttributableToLimitedPartnershipInterests": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail": { "order": 10020.0, "parentTag": "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding", "weight": 1.0 } }, "lang": { "en-US": { "role": { "documentation": "Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of limited partnership interests in BGC Holdings.", "label": "Incremental Common Shares Attributable To Limited Partnership Interests", "terseLabel": "Partnership units" } } }, "localname": "IncrementalCommonSharesAttributableToLimitedPartnershipInterests", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail" ], "xbrltype": "sharesItemType" }, "nmrk_IncrementalCommonSharesAttributableToOtherInstruments": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail": { "order": 10040.0, "parentTag": "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding", "weight": 1.0 } }, "lang": { "en-US": { "role": { "documentation": "Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of other instruments.", "label": "Incremental Common Shares Attributable To Other Instruments", "terseLabel": "Other" } } }, "localname": "IncrementalCommonSharesAttributableToOtherInstruments", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail" ], "xbrltype": "sharesItemType" }, "nmrk_IntercompanyCreditAgreementMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Intercompany credit agreement.", "label": "Intercompany Credit Agreement [Member]", "terseLabel": "Intercompany Credit Agreement [Member]" } } }, "localname": "IntercompanyCreditAgreementMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_InterestIncomeExpenseNetMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Interest income (expense), net.", "label": "Interest Income Expense Net [Member]", "terseLabel": "Interest Expense, Net [Member]", "verboseLabel": "Interest Expense, Net [Member]" } } }, "localname": "InterestIncomeExpenseNetMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_IssuanceAndRedemptionOfLimitedPartnershipUnitsIncludingContingentUnits": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Issuance and redemption of limited partnership units including contingent units.", "label": "Issuance And Redemption Of Limited Partnership Units Including Contingent Units", "terseLabel": "Issuance and redemption of limited partnership units including contingent units" } } }, "localname": "IssuanceAndRedemptionOfLimitedPartnershipUnitsIncludingContingentUnits", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "nmrk_IssuanceOfAdditionalLimitedPartnersUnitsInExchangeForCashPayment": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Issuance of additional limited partners units in exchange for cash payment.", "label": "Issuance Of Additional Limited Partners Units In Exchange For Cash Payment", "terseLabel": "Issuance of additional limited partners units in exchange for cash payment" } } }, "localname": "IssuanceOfAdditionalLimitedPartnersUnitsInExchangeForCashPayment", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_IssuanceOfLimitedPartnersUnitsExchanges": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Issuance of limited partners units exchanges.", "label": "Issuance Of Limited Partners Units Exchanges", "terseLabel": "Issuance of additional limited partners units in exchange" } } }, "localname": "IssuanceOfLimitedPartnersUnitsExchanges", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_IssuedPricePercentage": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Issued price percentage.", "label": "Issued Price Percentage", "terseLabel": "Issued price percentage" } } }, "localname": "IssuedPricePercentage", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_LeaseHoldImprovementsAndOtherFixedAssetsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Leasehold improvements and other fixed assets.", "label": "Lease Hold Improvements And Other Fixed Assets [Member]", "terseLabel": "Leasehold Improvements and Other Fixed Assets [Member]" } } }, "localname": "LeaseHoldImprovementsAndOtherFixedAssetsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "xbrltype": "domainItemType" }, "nmrk_LeasingAndOtherCommissionsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Leasing and other commissions.", "label": "Leasing And Other Commissions [Member]", "terseLabel": "Leasing and Other Commissions [Member]" } } }, "localname": "LeasingAndOtherCommissionsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail" ], "xbrltype": "domainItemType" }, "nmrk_LimitedPartnershipInterestDistributionRatio": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Limited partnership interest distribution ratio.", "label": "Limited Partnership Interest Distribution Ratio", "terseLabel": "Exchange Ratio Number of Common Shares Received Under Spin Off Transaction" } } }, "localname": "LimitedPartnershipInterestDistributionRatio", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_LimitedPartnershipInterestInitialContributionRatio": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Limited partnership interest initial contribution ratio.", "label": "Limited Partnership Interest Initial Contribution Ratio", "terseLabel": "Limited partnership interest initial contribution ratio" } } }, "localname": "LimitedPartnershipInterestInitialContributionRatio", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_LimitedPartnershipInterestSpinoffRatio": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Limited partnership interest spinoff ratio.", "label": "Limited Partnership Interest Spinoff Ratio", "terseLabel": "Exchange Ratio Number of Common Shares Received Under Spin Off Transaction" } } }, "localname": "LimitedPartnershipInterestSpinoffRatio", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_LimitedPartnershipInterestsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Limited partnership interests.", "label": "Limited Partnership Interests [Member]", "terseLabel": "Limited Partnership Interests [Member]" } } }, "localname": "LimitedPartnershipInterestsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_LimitedPartnershipUnitCashDistributions": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Limited partnership unit cash distributions.", "label": "Limited Partnership Unit Cash Distributions", "terseLabel": "Limited partnership unit cash distributions" } } }, "localname": "LimitedPartnershipUnitCashDistributions", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_LimitedPartnershipUnitsExchangeRatio": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Limited partnership units exchange ratio.", "label": "Limited Partnership Units Exchange Ratio", "terseLabel": "Limited partnership units exchange ratio" } } }, "localname": "LimitedPartnershipUnitsExchangeRatio", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "pureItemType" }, "nmrk_LimitedPartnershipUnitsHoldingsRatio": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Limited partnership units holdings ratio.", "label": "Limited Partnership Units Holdings Ratio", "terseLabel": "Limited partnership units holdings ratio" } } }, "localname": "LimitedPartnershipUnitsHoldingsRatio", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "pureItemType" }, "nmrk_LimitedPartnershipUnitsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Limited partnership units.", "label": "Limited Partnership Units [Member]", "terseLabel": "Limited Partnership Units [Member]" } } }, "localname": "LimitedPartnershipUnitsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_LineOfCreditFacilityCapacityAvailableBasedOnTemporaryAmount": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Line of credit facility capacity available based on temporary amount.", "label": "Line Of Credit Facility Capacity Available Based On Temporary Amount", "verboseLabel": "Facility available based on temporary amount" } } }, "localname": "LineOfCreditFacilityCapacityAvailableBasedOnTemporaryAmount", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_LineOfCreditFacilityTemporaryIncreaseDecreaseForPeriodNet": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of temporary increase (decrease) of the credit facility.", "label": "Line Of Credit Facility Temporary Increase Decrease For Period Net", "terseLabel": "Temporary facility increase (decrease) amount" } } }, "localname": "LineOfCreditFacilityTemporaryIncreaseDecreaseForPeriodNet", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_LoanAndLeaseReceivableBrokerageAmount": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Loan and lease receivable brokerage amount.", "label": "Loan And Lease Receivable Brokerage Amount", "terseLabel": "Loans receivable, brokerage service amount" } } }, "localname": "LoanAndLeaseReceivableBrokerageAmount", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_LoanReferralAgreementMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Loan referral agreement.", "label": "Loan Referral Agreement [Member]", "terseLabel": "Loan Referral Agreement [Member]" } } }, "localname": "LoanReferralAgreementMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_LoansAndLeasesReceivableMaturityDate": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Loans and leases receivable, maturity date.", "label": "Loans And Leases Receivable Maturity Date", "terseLabel": "Loan maturity date" } } }, "localname": "LoansAndLeasesReceivableMaturityDate", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "nmrk_LoansHeldForSaleCostBasis": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Loans held for sale cost basis.", "label": "Loans Held For Sale Cost Basis", "terseLabel": "Cost Basis" } } }, "localname": "LoansHeldForSaleCostBasis", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_LoansReceivableWithFixedRatesOfInterestPercentage": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Loans receivable with fixed rates of interest percentage.", "label": "Loans Receivable With Fixed Rates Of Interest Percentage", "terseLabel": "Loans receivable, fixed interest rate" } } }, "localname": "LoansReceivableWithFixedRatesOfInterestPercentage", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_LondonInterbankOfferedRateLIBOROrDefinedBaseRateMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "London interbank offered rate (L I B O R) or defined base rate.", "label": "London Interbank Offered Rate L I B O R Or Defined Base Rate [Member]", "terseLabel": "LIBOR or Defined Base Rate [Member]" } } }, "localname": "LondonInterbankOfferedRateLIBOROrDefinedBaseRateMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_LongTermEquityIncentivePlanMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Long term equity incentive plan.", "label": "Long Term Equity Incentive Plan [Member]", "terseLabel": "Newmark Equity Plan [Member]" } } }, "localname": "LongTermEquityIncentivePlanMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_MLGCommercialLLCMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "MLG Commercial LLC.", "label": "M L G Commercial L L C [Member]", "terseLabel": "MLG Commercial LLC [Member]" } } }, "localname": "MLGCommercialLLCMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ManagementServicesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Management services.", "label": "Management Services [Member]", "terseLabel": "Management Services [Member]" } } }, "localname": "ManagementServicesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail" ], "xbrltype": "domainItemType" }, "nmrk_ManagementServicesServicingFeesAndOther": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10180.0, "parentTag": "us-gaap_Revenues", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Management services, servicing fees and other.", "label": "Management Services Servicing Fees And Other", "terseLabel": "Management services, servicing fees and other" } } }, "localname": "ManagementServicesServicingFeesAndOther", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "nmrk_ManagementServicesServicingFeesAndOtherMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Management services, servicing fees and other.", "label": "Management Services Servicing Fees And Other [Member]", "terseLabel": "Management Services, Servicing Fees and Other [Member]" } } }, "localname": "ManagementServicesServicingFeesAndOtherMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_MarketableSecuritiesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Marketable securities.", "label": "Marketable Securities [Member]", "terseLabel": "Marketable Securities [Member]" } } }, "localname": "MarketableSecuritiesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_MarketableSecuritiesNumberOfSharesSold": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Marketable securities number of shares sold.", "label": "Marketable Securities Number Of Shares Sold", "verboseLabel": "Number of shares sold in transaction" } } }, "localname": "MarketableSecuritiesNumberOfSharesSold", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_MaximumPeriodOfLoansHeldForSaleSold": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Maximum period of loans held for sale sold.", "label": "Maximum Period Of Loans Held For Sale Sold", "terseLabel": "Maximum number of days loans held for sale are typically sold" } } }, "localname": "MaximumPeriodOfLoansHeldForSaleSold", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "nmrk_MaximumRevenueShareToRelatedPartyInFirstTwoYears": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Maximum revenue share to related party in first two years.", "label": "Maximum Revenue Share To Related Party In First Two Years", "terseLabel": "Maximum revenue share to related party in first two years" } } }, "localname": "MaximumRevenueShareToRelatedPartyInFirstTwoYears", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_MeasurementInputExpectedEarnoutAndContingenciesRateMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Measurement input expected earnout and contingencies rate.", "label": "Measurement Input Expected Earnout And Contingencies Rate [Member]", "terseLabel": "Measurement Input, Probability of Meeting Earnout and Contingencies [Member]" } } }, "localname": "MeasurementInputExpectedEarnoutAndContingenciesRateMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "nmrk_MiTNationalLandServicesLLCMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "MiT National Land Services, LLC [Member]", "label": "Mi T National Land Services L L C [Member]", "terseLabel": "MiT National Land Services LLC Acquisitions [Member]" } } }, "localname": "MiTNationalLandServicesLLCMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_MinorityInterestDecreaseFromRedemptionsOfExchangeablePartnershipUnits": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Minority interest decrease from redemptions of exchangeable partnership units.", "label": "Minority Interest Decrease From Redemptions Of Exchangeable Partnership Units", "negatedLabel": "Redemption of EPUs" } } }, "localname": "MinorityInterestDecreaseFromRedemptionsOfExchangeablePartnershipUnits", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "nmrk_MortgageServicingRightsLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Mortgage servicing rights.", "label": "Mortgage Servicing Rights [Line Items]", "terseLabel": "Mortgage Servicing Rights [Line Items]" } } }, "localname": "MortgageServicingRightsLineItems", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_MortgageServicingRightsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Mortgage servicing rights.", "label": "Mortgage Servicing Rights [Member]", "terseLabel": "Mortgage Servicing Rights [Member]" } } }, "localname": "MortgageServicingRightsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "domainItemType" }, "nmrk_MortgageServicingRightsTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Mortgage servicing rights.", "label": "Mortgage Servicing Rights [Table]", "terseLabel": "Mortgage Servicing Rights [Table]" } } }, "localname": "MortgageServicingRightsTable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_MortgageServicingRightsTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for mortgage servicing rights.", "label": "Mortgage Servicing Rights [Text Block]", "terseLabel": "Mortgage Servicing Rights, Net (\"MSRs\")" } } }, "localname": "MortgageServicingRightsTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrs" ], "xbrltype": "textBlockItemType" }, "nmrk_NasdaqMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Nasdaq.", "label": "Nasdaq [Member]", "terseLabel": "Nasdaq [Member]" } } }, "localname": "NasdaqMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NasdaqOMXForwardContractsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Nasdaq OMX forward contracts.", "label": "Nasdaq O M X Forward Contracts [Member]", "terseLabel": "Nasdaq Forward [Member]" } } }, "localname": "NasdaqOMXForwardContractsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "domainItemType" }, "nmrk_NasdaqOmxMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "NASDAQ OMX [Member]", "label": "Nasdaq Omx [Member]", "terseLabel": "NASDAQ [Member]", "verboseLabel": "NASDAQ [Member]" } } }, "localname": "NasdaqOmxMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NasdaqRecognition": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10360.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Nasdaq recognition.", "label": "Nasdaq Recognition", "terseLabel": "Nasdaq recognition" } } }, "localname": "NasdaqRecognition", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10260.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Net income loss after adjustments for noncash and nonoperating items.", "label": "Net Income Loss After Adjustments For Noncash And Nonoperating Items", "negatedTotalLabel": "Consolidated net income (loss), adjusted for non-cash and non-operating items" } } }, "localname": "NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "nmrk_NewmarkHoldingsLimitedPartnershipMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Newmark holdings limited partnership.", "label": "Newmark Holdings Limited Partnership [Member]", "terseLabel": "Newmark Holdings, L.P. [Member]" } } }, "localname": "NewmarkHoldingsLimitedPartnershipMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NewmarkHoldingsLimitedPartnershipUnitsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Newmark Holdings Limited Partnership units.", "label": "Newmark Holdings Limited Partnership Units [Member]", "terseLabel": "Newmark Holdings, L.P. [Member]" } } }, "localname": "NewmarkHoldingsLimitedPartnershipUnitsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NewmarkOpCoMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Newmark OpCo.", "label": "Newmark Op Co [Member]", "terseLabel": "Newmark OpCo [Member]" } } }, "localname": "NewmarkOpCoMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NewmarkUnitsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Newmark units.", "label": "Newmark Units [Member]", "terseLabel": "Newmark Units [Member]" } } }, "localname": "NewmarkUnitsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NonDistributionEarningUnitsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Non-distribution earning units.", "label": "Non Distribution Earning Units [Member]", "terseLabel": "N Units [Member]" } } }, "localname": "NonDistributionEarningUnitsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NonExchangeablePPSUMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Non Exchangeable Ppsu.", "label": "Non Exchangeable P P S U [Member]", "terseLabel": "Non-Exchangeable PPSU [Member]" } } }, "localname": "NonExchangeablePPSUMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NonExchangeableUnitsRedemptionValue": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Non-exchangeable units redemption value.", "label": "Non Exchangeable Units Redemption Value", "terseLabel": "Non-exchangeable units redemption, value" } } }, "localname": "NonExchangeableUnitsRedemptionValue", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_NonExecutiveMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Non executive.", "label": "Non Executive [Member]", "terseLabel": "Non Executive [Member]" } } }, "localname": "NonExecutiveMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_NonMarketableInvestments": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail": { "order": 10040.0, "parentTag": "us-gaap_OtherAssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Non marketable investments", "label": "Non Marketable Investments", "terseLabel": "Non-marketable investments" } } }, "localname": "NonMarketableInvestments", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_NoncontrollingInterestFromSubsidiaryEquityIssuanceShares": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Noncontrolling interest from subsidiary equity issuance, shares.", "label": "Noncontrolling Interest From Subsidiary Equity Issuance Shares", "terseLabel": "BGC's purchase of exchangeable limited partnership units in Newmark Holdings, shares" } } }, "localname": "NoncontrollingInterestFromSubsidiaryEquityIssuanceShares", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "sharesItemType" }, "nmrk_NoncontrollingInterestIncreaseDecreaseFromGrantOfExchangeabilityRedemptionAndIssuanceOfLimitedPartnershipInterests": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Noncontrolling interest increase (decrease) from grant of exchangeability redemption and issuance of limited partnership interests.", "label": "Noncontrolling Interest Increase Decrease From Grant Of Exchangeability Redemption And Issuance Of Limited Partnership Interests", "terseLabel": "Grant of exchangeability, redemption and issuance of limited partnership interests and issuance of common stock" } } }, "localname": "NoncontrollingInterestIncreaseDecreaseFromGrantOfExchangeabilityRedemptionAndIssuanceOfLimitedPartnershipInterests", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "nmrk_NotionalValueOfLimitedPartnershipUnitsWithPostTerminationPayOutAmount": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Notional value of limited partnership units with post termination pay out amount.", "label": "Notional Value Of Limited Partnership Units With Post Termination Pay Out Amount", "terseLabel": "Notional value with post-termination pay-out amount" } } }, "localname": "NotionalValueOfLimitedPartnershipUnitsWithPostTerminationPayOutAmount", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_NumberOfAuthorizedClassesOfCommonStock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of authorized classes of common stock.", "label": "Number Of Authorized Classes Of Common Stock", "terseLabel": "Number of authorized classes of common stock" } } }, "localname": "NumberOfAuthorizedClassesOfCommonStock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails" ], "xbrltype": "integerItemType" }, "nmrk_NumberOfEmployeesTransferred": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of employees transferred.", "label": "Number Of Employees Transferred", "terseLabel": "Number of employees transferred" } } }, "localname": "NumberOfEmployeesTransferred", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "integerItemType" }, "nmrk_NumberOfNetShareIssuedForNonExchangeableUnitsRedemption": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number Of Net Share Issued For Non Exchangeable Units Redemption.", "label": "Number Of Net Share Issued For Non Exchangeable Units Redemption", "terseLabel": "Number of net share issued for non exchangeable units redemption" } } }, "localname": "NumberOfNetShareIssuedForNonExchangeableUnitsRedemption", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_NumberOfNonExchangeablePSUApprovedCancellation": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of non-exchangeable PSU approved cancellation.", "label": "Number Of Non Exchangeable P S U Approved Cancellation", "terseLabel": "Number of non-exchangeable PSU approved cancellation" } } }, "localname": "NumberOfNonExchangeablePSUApprovedCancellation", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_NumberOfNonExchangeablePSUApprovedRedemption": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of non-exchangeable PSU approved redemption.", "label": "Number Of Non Exchangeable P S U Approved Redemption", "terseLabel": "Number of non-exchangeable psu approved redemption" } } }, "localname": "NumberOfNonExchangeablePSUApprovedRedemption", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_NumberOfNonExchangeableUnitsRedeemed": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of non-exchangeable units redeemed.", "label": "Number Of Non Exchangeable Units Redeemed", "terseLabel": "Number of non-exchangeable units redeemed" } } }, "localname": "NumberOfNonExchangeableUnitsRedeemed", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_NumberOfOfficesAcquired": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of offices acquired.", "label": "Number Of Offices Acquired", "terseLabel": "Number of offices acquired" } } }, "localname": "NumberOfOfficesAcquired", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "integerItemType" }, "nmrk_NumberOfShareIssuedForNonExchangeablePPSU": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number Of Share Issued For Non Exchangeable PPSU.", "label": "Number Of Share Issued For Non Exchangeable P P S U", "terseLabel": "Number of share issued for non exchangeable PPSU" } } }, "localname": "NumberOfShareIssuedForNonExchangeablePPSU", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_NumberOfSharesRemovedFromSaleRestriction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of shares removed from sale restriction.", "label": "Number Of Shares Removed From Sale Restriction", "terseLabel": "Number od shares removed from sale restriction" } } }, "localname": "NumberOfSharesRemovedFromSaleRestriction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_NumberOfUnitsConvertedToCommonStock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of units converted to common stock.", "label": "Number Of Units Converted To Common Stock", "verboseLabel": "Number of common shares under spin off transaction" } } }, "localname": "NumberOfUnitsConvertedToCommonStock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_OneMonthLondonInterbankOfferedRateLIBORMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "One month london interbank offered rate LIBOR.", "label": "One Month London Interbank Offered Rate L I B O R [Member]", "terseLabel": "One Month LIBOR [Member]" } } }, "localname": "OneMonthLondonInterbankOfferedRateLIBORMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_OperatingAdministrativeAndOtherMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Operating, administrative and other.", "label": "Operating Administrative And Other [Member]", "terseLabel": "Operating, Administrative and Other [Member]" } } }, "localname": "OperatingAdministrativeAndOtherMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_OptionsToPurchaseAdditionalSharesOfCommonStockPeriod": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Options to purchase additional shares of common stock period.", "label": "Options To Purchase Additional Shares Of Common Stock Period", "terseLabel": "Options to purchase additional shares of common stock period" } } }, "localname": "OptionsToPurchaseAdditionalSharesOfCommonStockPeriod", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "nmrk_OutsideBrokerPayableCurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": 10030.0, "parentTag": "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Outside broker payable, current.", "label": "Outside Broker Payable Current", "terseLabel": "Outside broker payable" } } }, "localname": "OutsideBrokerPayableCurrent", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_OutstandingBorrowerAdvancesToInvestors": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Outstanding borrower advances to investors.", "label": "Outstanding Borrower Advances To Investors", "terseLabel": "Outstanding borrower advances" } } }, "localname": "OutstandingBorrowerAdvancesToInvestors", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_OwnershipInterestPercentage": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of ownership interests.", "label": "Ownership Interest Percentage", "terseLabel": "Ownership interest percentage" } } }, "localname": "OwnershipInterestPercentage", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PaymentRelatedTaxRateForCommonStock": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Payment related tax rate for common stock.", "label": "Payment Related Tax Rate For Common Stock", "terseLabel": "Payment of withholding tax rate for common stock issue" } } }, "localname": "PaymentRelatedTaxRateForCommonStock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_PaymentRelatedToWithholdingTaxRateForCommonSharesIssued": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Payment Related To Withholding Tax Rate For Common Shares Issued.", "label": "Payment Related To Withholding Tax Rate For Common Shares Issued", "terseLabel": "Payment related to withholding tax rate for common shares issued" } } }, "localname": "PaymentRelatedToWithholdingTaxRateForCommonSharesIssued", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_PaymentsToAcquireNonMarketableInvestments": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10230.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Payments to acquire non-marketable investments.", "label": "Payments To Acquire Non Marketable Investments", "negatedLabel": "Purchases of non-marketable investments" } } }, "localname": "PaymentsToAcquireNonMarketableInvestments", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "nmrk_PercentageOfContingentLiabilityOfActualLossesIncurredOnOutstandingLoans": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of contingent liability of actual losses incurred on outstanding loans.", "label": "Percentage Of Contingent Liability Of Actual Losses Incurred On Outstanding Loans", "terseLabel": "Percentage of contingent liability of actual losses incurred on outstanding loans" } } }, "localname": "PercentageOfContingentLiabilityOfActualLossesIncurredOnOutstandingLoans", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfContingentPayment": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of contingent payment.", "label": "Percentage Of Contingent Payment", "terseLabel": "Percentage of contingent payment" } } }, "localname": "PercentageOfContingentPayment", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfDistributionsOfShares": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of Distributions of shares in spin-off", "label": "Percentage Of Distributions Of Shares", "terseLabel": "Percentage of Distributions of shares in spin-off" } } }, "localname": "PercentageOfDistributionsOfShares", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfGrossProceedPaidForUnderwriter": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of gross proceed paid for underwriter.", "label": "Percentage Of Gross Proceed Paid For Underwriter", "terseLabel": "Percentage of gross proceeds paid to underwriter" } } }, "localname": "PercentageOfGrossProceedPaidForUnderwriter", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfIncreaseInDiscountRateOfServicingRights": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of increase in discount rate of servicing rights.", "label": "Percentage Of Increase In Discount Rate Of Servicing Rights", "terseLabel": "Increase in discount rate" } } }, "localname": "PercentageOfIncreaseInDiscountRateOfServicingRights", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfLiquidityRequirementOfOutstandingPrincipalOfTargetedAffordableHousingLoansServiced": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of liquidity requirement of outstanding principal of targeted affordable housing loans serviced.", "label": "Percentage Of Liquidity Requirement Of Outstanding Principal Of Targeted Affordable Housing Loans Serviced", "terseLabel": "Percentage of Freddie Mac's liquidity requirement of outstanding principal of TAH loans serviced" } } }, "localname": "PercentageOfLiquidityRequirementOfOutstandingPrincipalOfTargetedAffordableHousingLoansServiced", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfOwnershipInterestOfLoansReceivable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of ownership interest of loans receivable.", "label": "Percentage Of Ownership Interest Of Loans Receivable", "terseLabel": "Percentage of ownership interest of loan receivable" } } }, "localname": "PercentageOfOwnershipInterestOfLoansReceivable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfProfitsAllocatedToPreferredPartnershipUnits": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of profits allocated to preferred partnership units.", "label": "Percentage Of Profits Allocated To Preferred Partnership Units", "terseLabel": "Percentage to preferred units" } } }, "localname": "PercentageOfProfitsAllocatedToPreferredPartnershipUnits", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfThirdPartyBankPurchasedLoanValue": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of third party bank purchased loan value.", "label": "Percentage Of Third Party Bank Purchased Loan Value", "terseLabel": "Percentage of third party bank purchased loan value" } } }, "localname": "PercentageOfThirdPartyBankPurchasedLoanValue", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PercentageOfThirdPartyBankRetainingLoanValue": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Percentage of third party bank retaining loan value.", "label": "Percentage Of Third Party Bank Retaining Loan Value", "terseLabel": "Percentage of third party bank retaining loan value" } } }, "localname": "PercentageOfThirdPartyBankRetainingLoanValue", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "nmrk_PeriodForEarnOutReceivableUnderCommonStockTransaction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Period for earn out receivable under common stock transaction.", "label": "Period For Earn Out Receivable Under Common Stock Transaction", "terseLabel": "Period for earn-out receivable under common stock transaction" } } }, "localname": "PeriodForEarnOutReceivableUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "nmrk_PeriodForPaymentUnderCommonStockTransaction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Period for payment under common stock transaction.", "label": "Period For Payment Under Common Stock Transaction", "terseLabel": "Period for expected payment under Common stock transaction" } } }, "localname": "PeriodForPaymentUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "nmrk_PostTerminationAwardPayoutPeriod": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Post termination award payout period.", "label": "Post Termination Award Payout Period", "terseLabel": "Payout period for post-termination awards" } } }, "localname": "PostTerminationAwardPayoutPeriod", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_PreferredUnitsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Preferred Units [Member].", "label": "Preferred Units [Member]", "terseLabel": "Preferred Units [Member]" } } }, "localname": "PreferredUnitsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_PrepaymentPenalty": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Prepayment penalty.", "label": "Prepayment Penalty", "terseLabel": "Prepayment penalty" } } }, "localname": "PrepaymentPenalty", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_PrimaryServicingPortfolio": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Primary servicing portfolio.", "label": "Primary Servicing Portfolio", "terseLabel": "Primary servicing portfolio" } } }, "localname": "PrimaryServicingPortfolio", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_PrimaryServicingRightsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Primary servicing rights.", "label": "Primary Servicing Rights [Member]", "terseLabel": "Primary Servicing Rights [Member]" } } }, "localname": "PrimaryServicingRightsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ProceedsFromIssuanceOfAdditionalLimitedPartnersUnitsWithCapitalAccount": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Proceeds from issuance of additional limited partners units with capital account.", "label": "Proceeds From Issuance Of Additional Limited Partners Units With Capital Account", "terseLabel": "Issuance of additional limited partnership units with capital account" } } }, "localname": "ProceedsFromIssuanceOfAdditionalLimitedPartnersUnitsWithCapitalAccount", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ProceedsFromLimitedPartnershipUnits": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Proceeds from limited partnership units.", "label": "Proceeds From Limited Partnership Units", "terseLabel": "Proceeds from limited partnership units" } } }, "localname": "ProceedsFromLimitedPartnershipUnits", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ProceedsFromSettlementOfPreSpinOffRelatedPartyReceivables": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10100.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Proceeds from settlement of pre spin-off related party receivables.", "label": "Proceeds From Settlement Of Pre Spin Off Related Party Receivables", "terseLabel": "Settlement of pre-Spin-Off related party receivables" } } }, "localname": "ProceedsFromSettlementOfPreSpinOffRelatedPartyReceivables", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "nmrk_ProvisionForRiskSharingObligations": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Provision for risk-sharing obligations.", "label": "Provision For Risk Sharing Obligations", "totalLabel": "Total" } } }, "localname": "ProvisionForRiskSharingObligations", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfProvisionsForRiskSharingDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_RKFRetailHoldingsLLCMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "RKF Retail Holdings, LLC.", "label": "R K F Retail Holdings L L C [Member]", "terseLabel": "RKF Retail Holdings LLC Acquisitions [Member]" } } }, "localname": "RKFRetailHoldingsLLCMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_RealizedGainLossOnNonmarketableInvestments": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10410.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Realized gain loss on nonmarketable investments.", "label": "Realized Gain Loss On Nonmarketable Investments", "negatedLabel": "Realized gain on non-marketable investments, net" } } }, "localname": "RealizedGainLossOnNonmarketableInvestments", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "nmrk_RecentlyAdoptedAccountingPronouncementsPolicyTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Recently Adopted Accounting Pronouncements Policy.", "label": "Recently Adopted Accounting Pronouncements Policy [Text Block]", "terseLabel": "Recently Adopted Accounting Pronouncements" } } }, "localname": "RecentlyAdoptedAccountingPronouncementsPolicyTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationPolicies" ], "xbrltype": "textBlockItemType" }, "nmrk_ReclassificationOfExchangeablePreferredPartnershipUnitsFromNoncontrollingInterestsToPayable": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Reclassification of exchangeable preferred partnership units from noncontrolling interests to payable.", "label": "Reclassification Of Exchangeable Preferred Partnership Units From Noncontrolling Interests To Payable", "terseLabel": "Reclassified of EPU from noncontrolling interests to payable" } } }, "localname": "ReclassificationOfExchangeablePreferredPartnershipUnitsFromNoncontrollingInterestsToPayable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_RedeemableExchangeablePartnershipUnitsCurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": 10020.0, "parentTag": "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Redeemable exchangeable partnership units current.", "label": "Redeemable Exchangeable Partnership Units Current", "terseLabel": "Redeemable EPUs" } } }, "localname": "RedeemableExchangeablePartnershipUnitsCurrent", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ReductionOfEarningsDistributions": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Reduction of earnings distributions.", "label": "Reduction Of Earnings Distributions", "terseLabel": "Reduction of earning distributions" } } }, "localname": "ReductionOfEarningsDistributions", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "nmrk_ReimbursementsUnderServicingAgreement": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Reimbursements under servicing agreement.", "label": "Reimbursements Under Servicing Agreement", "terseLabel": "Reimbursements under servicing agreement" } } }, "localname": "ReimbursementsUnderServicingAgreement", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_RelatedPartyTransactionLimitOnLoanNotYetAcquiredOrSold": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Related party transaction limit on loan not yet acquired or sold.", "label": "Related Party Transaction Limit On Loan Not Yet Acquired Or Sold", "terseLabel": "Related party transaction limit on loan not yet acquired or sold" } } }, "localname": "RelatedPartyTransactionLimitOnLoanNotYetAcquiredOrSold", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_RelatedPartyTransactionLimitOnLoanOutstanding": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Related party transaction limit on loan outstanding.", "label": "Related Party Transaction Limit On Loan Outstanding", "terseLabel": "Related party transaction limit on loan outstanding" } } }, "localname": "RelatedPartyTransactionLimitOnLoanOutstanding", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_RelatedPartyTransactionMaximumAmountPerLoan": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Related party transaction maximum amount per loan.", "label": "Related Party Transaction Maximum Amount Per Loan", "terseLabel": "Related party transaction maximum amount per loan" } } }, "localname": "RelatedPartyTransactionMaximumAmountPerLoan", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_RelatedPartyTransactionServiceFeesPaid": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Related party transaction service fees paid.", "label": "Related Party Transaction Service Fees Paid", "terseLabel": "Related party transaction, service fees paid" } } }, "localname": "RelatedPartyTransactionServiceFeesPaid", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_RelatedPartyTransactionsBrokerFeesAndCommissions": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Related party transactions broker fees and commissions.", "label": "Related Party Transactions Broker Fees And Commissions", "terseLabel": "Broker fees and commissions" } } }, "localname": "RelatedPartyTransactionsBrokerFeesAndCommissions", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_RemainingEarnOutSharesReceivableUnderCommonStockTransaction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Remaining earn out shares receivable under common stock transaction.", "label": "Remaining Earn Out Shares Receivable Under Common Stock Transaction", "terseLabel": "Remaining earn-out receivable under common stock transaction" } } }, "localname": "RemainingEarnOutSharesReceivableUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_RemainingNumberOfEarnOutSharesReceivedUnderCommonStockTransaction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Remaining number of earn-out shares received under common stock transaction.", "label": "Remaining Number Of Earn Out Shares Received Under Common Stock Transaction", "terseLabel": "Remaining number of earn-out shares received under common stock transaction" } } }, "localname": "RemainingNumberOfEarnOutSharesReceivedUnderCommonStockTransaction", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_RestrictedStockUnitsVestingDescription": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Restricted Stock Units Vesting Description", "label": "Restricted Stock Units Vesting Description", "terseLabel": "Restricted stock unit, Conversion description" } } }, "localname": "RestrictedStockUnitsVestingDescription", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_RevenueFromContractWithCustomersTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Revenue from contract with customers.", "label": "Revenue From Contract With Customers [Table]", "terseLabel": "Revenue From Contract With Customers [Table]" } } }, "localname": "RevenueFromContractWithCustomersTable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail" ], "xbrltype": "stringItemType" }, "nmrk_ScheduleOfAccountsPayableAccruedLiabilitiesAndOtherLiabilitiesCurrentTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule of accounts payable, accrued liabilities and other liabilities, current.", "label": "Schedule Of Accounts Payable Accrued Liabilities And Other Liabilities Current Table [Text Block]", "terseLabel": "Components of Current Portion of Accounts Payable, Accrued Expenses and Other Liabilities" } } }, "localname": "ScheduleOfAccountsPayableAccruedLiabilitiesAndOtherLiabilitiesCurrentTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesTables" ], "xbrltype": "textBlockItemType" }, "nmrk_ScheduleOfAcquiredFiniteAndIndefiniteLivedIntangibleAssetByMajorClassLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule of acquired finite and indefinite lived intangible asset by major class.", "label": "Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]", "terseLabel": "Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]" } } }, "localname": "ScheduleOfAcquiredFiniteAndIndefiniteLivedIntangibleAssetByMajorClassLineItems", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "stringItemType" }, "nmrk_ScheduleOfAcquiredFiniteAndIndefiniteLivedIntangibleAssetByMajorClassTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule of acquired finite and indefinite lived intangible asset by major class.", "label": "Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Table]", "terseLabel": "Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Table]" } } }, "localname": "ScheduleOfAcquiredFiniteAndIndefiniteLivedIntangibleAssetByMajorClassTable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "stringItemType" }, "nmrk_ScheduleOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostInitialPublicOfferingGrantsTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule of activity of number of share equivalent limited partnership units and post initial public offering grants.", "label": "Schedule Of Activity Of Number Of Share Equivalent Limited Partnership Units And Post Initial Public Offering Grants Table [Text Block]", "terseLabel": "Summary of Activity of Number of Share Equivalent Limited Partnership Units and Post IPO Grants" } } }, "localname": "ScheduleOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostInitialPublicOfferingGrantsTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables" ], "xbrltype": "textBlockItemType" }, "nmrk_ScheduleOfLoansHeldForSaleTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule of loans held for sale.", "label": "Schedule Of Loans Held For Sale Table [Text Block]", "terseLabel": "Summary of Loans Held for Sale at Cost Basis and Fair Value" } } }, "localname": "ScheduleOfLoansHeldForSaleTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueTables" ], "xbrltype": "textBlockItemType" }, "nmrk_ScheduleOfProvisionForRiskSharingObligationsTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule of provision for risk sharing obligations.", "label": "Schedule Of Provision For Risk Sharing Obligations Table [Text Block]", "terseLabel": "Schedule of Provision for Risk Sharing" } } }, "localname": "ScheduleOfProvisionForRiskSharingObligationsTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityTables" ], "xbrltype": "textBlockItemType" }, "nmrk_ScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule of revenues from contracts with customers and other sources of revenues.", "label": "Schedule Of Revenues From Contracts With Customers And Other Sources Of Revenues Table [Text Block]", "terseLabel": "Schedule of Revenues from Contracts with Customers and Other Sources of Revenues" } } }, "localname": "ScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersTables" ], "xbrltype": "textBlockItemType" }, "nmrk_ScheduleOfShareRepurchaseActivityTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Schedule of share repurchase activity.", "label": "Schedule Of Share Repurchase Activity Table [Text Block]", "terseLabel": "Schedule of Share Repurchase Activity" } } }, "localname": "ScheduleOfShareRepurchaseActivityTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsTables" ], "xbrltype": "textBlockItemType" }, "nmrk_SecuritiesLoanedDisclosureTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Securities loaned disclosure.", "label": "Securities Loaned Disclosure [Text Block]", "terseLabel": "Securities Loaned" } } }, "localname": "SecuritiesLoanedDisclosureTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoaned" ], "xbrltype": "textBlockItemType" }, "nmrk_SecurityDepositReturnDate": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Security deposit return date.", "label": "Security Deposit Return Date", "terseLabel": "Security deposit return date" } } }, "localname": "SecurityDepositReturnDate", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "nmrk_SellerServicerAgreementsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Seller servicer agreements.", "label": "Seller Servicer Agreements [Member]", "terseLabel": "Seller/Servicer Agreements [Member]" } } }, "localname": "SellerServicerAgreementsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ServicingAssetAtAmortizedValuePurchasesFromAffiliate": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Servicing asset at amortized value purchases from affiliate.", "label": "Servicing Asset At Amortized Value Purchases From Affiliate", "terseLabel": "Purchases from an affiliate" } } }, "localname": "ServicingAssetAtAmortizedValuePurchasesFromAffiliate", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ServicingFeesAndOtherRevenue": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail": { "order": 10030.0, "parentTag": "us-gaap_Revenues", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Servicing fees and other revenue.", "label": "Servicing Fees And Other Revenue", "terseLabel": "Servicing fees and other" } } }, "localname": "ServicingFeesAndOtherRevenue", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingGrantDateFairValue": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Share based compensation arrangement by share based payment award equity instruments other than options outstanding grant date fair value.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Grant Date Fair Value", "terseLabel": "Aggregate estimated grant date fair values" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingGrantDateFairValue", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentRedeemedExchanged": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of exchangeable limited partnership units redeemed or exchanged into the Company's class A common stock during the period.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instrument Redeemed Exchanged", "negatedLabel": "Number of Units, Redeemed/exchanged units", "terseLabel": "Number of limited partnership units exchangeable" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentRedeemedExchanged", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeituresAndOther": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Share-based compensation arrangement by share-based payment award non option equity instruments forfeitures and other.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Forfeitures And Other", "terseLabel": "Number of Units, Forfeited units/Other units" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeituresAndOther", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail" ], "xbrltype": "sharesItemType" }, "nmrk_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesRegistered": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Share-based compensation arrangement by share-based payment award, number of shares registered.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Registered", "terseLabel": "Shares registered to be delivered pursuant to awards granted" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesRegistered", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_ShareBasedCompensationArrangementByShareBasedPaymentAwardUnitsRedeemed": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Share based compensation arrangement by share based payment award units redeemed.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Units Redeemed", "terseLabel": "Number of units redeemed" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardUnitsRedeemed", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_ShareBasedCompensationExpenseRelatedToUnitsRedeemed": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Share based compensation expense related to units redeemed.", "label": "Share Based Compensation Expense Related To Units Redeemed", "terseLabel": "Expense related to units redeemed" } } }, "localname": "ShareBasedCompensationExpenseRelatedToUnitsRedeemed", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_ShareEquivalentLimitedPartnershipUnitsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Share-equivalent limited partnership units.", "label": "Share Equivalent Limited Partnership Units [Member]", "terseLabel": "Share Equivalent Limited Partnership Units [Member]" } } }, "localname": "ShareEquivalentLimitedPartnershipUnitsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail" ], "xbrltype": "domainItemType" }, "nmrk_ShareRepurchaseAndRedemptionUnitRemainingAuthorizedAmount": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Share repurchase and redemption unit remaining authorized amount.", "label": "Share Repurchase And Redemption Unit Remaining Authorized Amount", "terseLabel": "Share repurchase and redemption unit remaining authorized amount", "verboseLabel": "Approximate Dollar Value of Units and Shares That May Yet Be Redeemed/Purchased Under the Plan" } } }, "localname": "ShareRepurchaseAndRedemptionUnitRemainingAuthorizedAmount", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_SixPointOneTwoFivePercentSeniorNotesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Six point one two five percent senior notes.", "label": "Six Point One Two Five Percent Senior Notes [Member]", "terseLabel": "6.125% Senior Notes [Member]" } } }, "localname": "SixPointOneTwoFivePercentSeniorNotesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_SpecialServicingPortfolio": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Special servicing portfolio.", "label": "Special Servicing Portfolio", "terseLabel": "Special servicing portfolio" } } }, "localname": "SpecialServicingPortfolio", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_StockRepurchaseProgramNumberOfSharesAnnouncedToBeRepurchased": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Stock repurchase program, number of shares announced to be repurchased.", "label": "Stock Repurchase Program Number Of Shares Announced To Be Repurchased", "terseLabel": "Total Number of Shares Purchased as Part of Publicly Announced Program" } } }, "localname": "StockRepurchaseProgramNumberOfSharesAnnouncedToBeRepurchased", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail" ], "xbrltype": "sharesItemType" }, "nmrk_StockRepurchasesAndRedeemedOrRepurchasesAuthorizedAmount": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Stock repurchases and redeemed or repurchases authorized amount.", "label": "Stock Repurchases And Redeemed Or Repurchases Authorized Amount", "terseLabel": "Stock repurchases and redeemed or repurchases authorized amount" } } }, "localname": "StockRepurchasesAndRedeemedOrRepurchasesAuthorizedAmount", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails" ], "xbrltype": "monetaryItemType" }, "nmrk_StraightLineMethodMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Straight line method.", "label": "Straight Line Method [Member]", "terseLabel": "Straight Line Method [Member]" } } }, "localname": "StraightLineMethodMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_SummaryOfGainsFromMortgageBankingActivitiesNetTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Summary of gains from mortgage banking activities, net.", "label": "Summary Of Gains From Mortgage Banking Activities Net Table [Text Block]", "terseLabel": "Summary Of Gains From Mortgage Banking Activities, Net" } } }, "localname": "SummaryOfGainsFromMortgageBankingActivitiesNetTableTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetTables" ], "xbrltype": "textBlockItemType" }, "nmrk_SummaryOfSignificantAccountingPoliciesLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Summary of significant accounting policies.", "label": "Summary Of Significant Accounting Policies [Line Items]", "terseLabel": "Summary Of Significant Accounting Policies [Line Items]" } } }, "localname": "SummaryOfSignificantAccountingPoliciesLineItems", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_SummaryOfSignificantAccountingPoliciesTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Summary of significant accounting policies.", "label": "Summary Of Significant Accounting Policies [Table]", "terseLabel": "Summary Of Significant Accounting Policies [Table]" } } }, "localname": "SummaryOfSignificantAccountingPoliciesTable", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "nmrk_TermLoanMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Term loan.", "label": "Term Loan [Member]", "terseLabel": "Term Loan [Member]" } } }, "localname": "TermLoanMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail" ], "xbrltype": "domainItemType" }, "nmrk_TheRoyalBankOfCanadaMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The Royal Bank Of Canada.", "label": "The Royal Bank Of Canada [Member]", "terseLabel": "RBC [Member]" } } }, "localname": "TheRoyalBankOfCanadaMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_ThirdPartyBankAndCantorCommercialRealEstateLPMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "third-party bank and Cantor Commercial Real Estate, L.P.", "label": "Third Party Bank And Cantor Commercial Real Estate L P [Member]", "terseLabel": "CCRE Lending [Member]" } } }, "localname": "ThirdPartyBankAndCantorCommercialRealEstateLPMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_TwoThousandAndFortyTwoPromissoryNotesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Two thousand and forty two promissory notes.", "label": "Two Thousand And Forty Two Promissory Notes [Member]", "terseLabel": "2042 Promissory Note [Member]" } } }, "localname": "TwoThousandAndFortyTwoPromissoryNotesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_TwoThousandAndNineteenPromissoryNotesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Two thousand and nineteen promissory notes.", "label": "Two Thousand And Nineteen Promissory Notes [Member]", "terseLabel": "2019 Promissory Note [Member]" } } }, "localname": "TwoThousandAndNineteenPromissoryNotesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "nmrk_TwoThousandEighteenAcquisitionsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Two Thousand Eighteen Acquisitions [Member]", "terseLabel": "Two Thousand Eighteen Acquisitions [Member]" } } }, "localname": "TwoThousandEighteenAcquisitionsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "domainItemType" }, "nmrk_TwoThousandNineteenAcquisitionsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Two thousand nineteen acquisitions.", "label": "Two Thousand Nineteen Acquisitions [Member]", "terseLabel": "Two Thousand Nineteen Acquisitions [Member]" } } }, "localname": "TwoThousandNineteenAcquisitionsMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "domainItemType" }, "nmrk_UncommittedLinesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Uncommitted lines.", "label": "Uncommitted Lines [Member]", "terseLabel": "Uncommitted Lines [Member]" } } }, "localname": "UncommittedLinesMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "domainItemType" }, "nmrk_UnderwriterOverallotmentOptionToPurchaseCommonStockNumberExercised": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Underwriter overallotment option to purchase common stock number exercised.", "label": "Underwriter Overallotment Option To Purchase Common Stock Number Exercised", "terseLabel": "Option to purchase additional shares" } } }, "localname": "UnderwriterOverallotmentOptionToPurchaseCommonStockNumberExercised", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "nmrk_UnrealizedGainsLossOnLoansHeldForSale": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10420.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Unrealized gains loss on loans held for sale.", "label": "Unrealized Gains Loss On Loans Held For Sale", "negatedLabel": "Unrealized gains on loans held for sale" } } }, "localname": "UnrealizedGainsLossOnLoansHeldForSale", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "nmrk_ValueOfLPUIssuedInExchange": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Value of LPU issued in exchange.", "label": "Value Of L P U Issued In Exchange", "terseLabel": "Value of LPU issued in exchange" } } }, "localname": "ValueOfLPUIssuedInExchange", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "nmrk_WarehouseFacilityDueJuneNineteenTwoThousandNineteenMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Warehouse facility due june nineteen two thousand nineteen.", "label": "Warehouse Facility Due June Nineteen Two Thousand Nineteen [Member]", "terseLabel": "Warehouse Facility Due June 19, 2019 [Member]" } } }, "localname": "WarehouseFacilityDueJuneNineteenTwoThousandNineteenMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "nmrk_WarehouseFacilityDueJuneSeventeenTwoThousandTwentyMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Warehouse facility due June 17, 2020.", "label": "Warehouse Facility Due June Seventeen Two Thousand Twenty [Member]", "terseLabel": "Warehouse Facility Due June 17, 2020 [Member]" } } }, "localname": "WarehouseFacilityDueJuneSeventeenTwoThousandTwentyMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "nmrk_WarehouseFacilityDueJuneSeventeenTwoThousandTwentyOneMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Warehouse facility due June seventeen two thousand twenty one.", "label": "Warehouse Facility Due June Seventeen Two Thousand Twenty One [Member]", "terseLabel": "Warehouse Facility Due June 17, 2020 [Member]" } } }, "localname": "WarehouseFacilityDueJuneSeventeenTwoThousandTwentyOneMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "nmrk_WarehouseFacilityDueOctoberNineTwoThousandAndTwentyMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Warehouse facility due October 9, 2020.", "label": "Warehouse Facility Due October Nine Two Thousand And Twenty [Member]", "terseLabel": "Warehouse Facility Due October 9, 2020 [Member]" } } }, "localname": "WarehouseFacilityDueOctoberNineTwoThousandAndTwentyMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "nmrk_WarehouseFacilityDueOctoberTenTwoThousandAndNineteenMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Warehouse facility due October 10, 2019.", "label": "Warehouse Facility Due October Ten Two Thousand And Nineteen [Member]", "terseLabel": "Warehouse Facility Due October 10, 2019 [Member]" } } }, "localname": "WarehouseFacilityDueOctoberTenTwoThousandAndNineteenMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "nmrk_WarehouseFacilityDueSeptemberTwentyFiveTwoThousandNineteenMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Warehouse facility due September 25, 2019.", "label": "Warehouse Facility Due September Twenty Five Two Thousand Nineteen [Member]", "terseLabel": "Warehouse Facility Due September 25, 2019 [Member]" } } }, "localname": "WarehouseFacilityDueSeptemberTwentyFiveTwoThousandNineteenMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "nmrk_WarehouseFacilityDueSeptemberTwentyFiveTwoThousandTwentyMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Warehouse facility due September 25, 2020.", "label": "Warehouse Facility Due September Twenty Five Two Thousand Twenty [Member]", "terseLabel": "Warehouse Facility Due September 25, 2020 [Member]" } } }, "localname": "WarehouseFacilityDueSeptemberTwentyFiveTwoThousandTwentyMember", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "nmrk_WarehouseLinesOfCreditTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for warehouse lines of credit.", "label": "Warehouse Lines Of Credit [Text Block]", "terseLabel": "Warehouse Facilities Collateralized by U.S. Government Sponsored Enterprises" } } }, "localname": "WarehouseLinesOfCreditTextBlock", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprises" ], "xbrltype": "textBlockItemType" }, "nmrk_YieldPercentage": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Yield percentage.", "label": "Yield Percentage", "terseLabel": "Yield percentage" } } }, "localname": "YieldPercentage", "nsuri": "http://www.ngkf.com/20190930", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "srt_AffiliatedEntityMember": { "auth_ref": [ "r274", "r429", "r431", "r535" ], "lang": { "en-US": { "role": { "label": "Affiliated Entity [Member]", "terseLabel": "Affiliated Persons or Entities [Member]" } } }, "localname": "AffiliatedEntityMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails" ], "xbrltype": "domainItemType" }, "srt_BrokersAndDealersAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Brokers And Dealers [Abstract]" } } }, "localname": "BrokersAndDealersAbstract", "nsuri": "http://fasb.org/srt/2019-01-31", "xbrltype": "stringItemType" }, "srt_ChiefExecutiveOfficerMember": { "auth_ref": [ "r159" ], "lang": { "en-US": { "role": { "label": "Chief Executive Officer [Member]", "terseLabel": "Chief Executive Officer [Member]" } } }, "localname": "ChiefExecutiveOfficerMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_ConsolidatedEntitiesAxis": { "auth_ref": [ "r535" ], "lang": { "en-US": { "role": { "label": "Consolidated Entities [Axis]", "terseLabel": "Consolidated Entities" } } }, "localname": "ConsolidatedEntitiesAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "srt_ConsolidatedEntitiesDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Consolidated Entities [Domain]", "terseLabel": "Consolidated Entities" } } }, "localname": "ConsolidatedEntitiesDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_CounterpartyNameAxis": { "auth_ref": [ "r61", "r116" ], "lang": { "en-US": { "role": { "label": "Counterparty Name [Axis]", "terseLabel": "Counterparty Name" } } }, "localname": "CounterpartyNameAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "srt_EquityMethodInvesteeNameDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Equity Method Investee Name [Domain]", "terseLabel": "Investment, Name" } } }, "localname": "EquityMethodInvesteeNameDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_MaximumMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Maximum [Member]", "terseLabel": "Maximum [Member]" } } }, "localname": "MaximumMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_MinimumMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Minimum [Member]", "terseLabel": "Minimum [Member]" } } }, "localname": "MinimumMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_OwnershipAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Ownership [Axis]", "terseLabel": "Ownership" } } }, "localname": "OwnershipAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "srt_OwnershipDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Ownership [Domain]", "terseLabel": "Ownership" } } }, "localname": "OwnershipDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_ParentCompanyMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Parent Company [Member]", "terseLabel": "NEWMARK Group Inc Parent [Member]" } } }, "localname": "ParentCompanyMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_ProductOrServiceAxis": { "auth_ref": [ "r157", "r263", "r266", "r518", "r519" ], "lang": { "en-US": { "role": { "label": "Product Or Service [Axis]", "terseLabel": "Product and Service" } } }, "localname": "ProductOrServiceAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail" ], "xbrltype": "stringItemType" }, "srt_ProductsAndServicesDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Products And Services [Domain]", "terseLabel": "Product and Service" } } }, "localname": "ProductsAndServicesDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail" ], "xbrltype": "domainItemType" }, "srt_RangeAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Range [Axis]", "terseLabel": "Statistical Measurement" } } }, "localname": "RangeAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "srt_RangeMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Range [Member]", "terseLabel": "Statistical Measurement" } } }, "localname": "RangeMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_RegulatoryCapitalRequirementsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Regulatory Capital Requirements [Abstract]" } } }, "localname": "RegulatoryCapitalRequirementsAbstract", "nsuri": "http://fasb.org/srt/2019-01-31", "xbrltype": "stringItemType" }, "srt_RepurchaseAgreementCounterpartyNameDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Repurchase Agreement Counterparty Name [Domain]", "terseLabel": "Counterparty Name" } } }, "localname": "RepurchaseAgreementCounterpartyNameDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_ScenarioForecastMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Scenario Forecast [Member]", "terseLabel": "Scenario, Forecast [Member]" } } }, "localname": "ScenarioForecastMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_ScenarioUnspecifiedDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Scenario Unspecified [Domain]", "terseLabel": "Scenario" } } }, "localname": "ScenarioUnspecifiedDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis": { "auth_ref": [ "r170" ], "lang": { "en-US": { "role": { "label": "Schedule Of Equity Method Investment Equity Method Investee Name [Axis]", "terseLabel": "Investment, Name" } } }, "localname": "ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "srt_SegmentGeographicalDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Segment Geographical [Domain]", "terseLabel": "Geographical" } } }, "localname": "SegmentGeographicalDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_StatementGeographicalAxis": { "auth_ref": [ "r158", "r263", "r267", "r520", "r533", "r534" ], "lang": { "en-US": { "role": { "label": "Statement Geographical [Axis]", "terseLabel": "Geographical" } } }, "localname": "StatementGeographicalAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "srt_StatementScenarioAxis": { "auth_ref": [ "r222", "r437" ], "lang": { "en-US": { "role": { "label": "Statement Scenario [Axis]", "terseLabel": "Scenario" } } }, "localname": "StatementScenarioAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "srt_TitleOfIndividualAxis": { "auth_ref": [ "r159", "r430" ], "lang": { "en-US": { "role": { "label": "Title Of Individual [Axis]", "terseLabel": "Title of Individual" } } }, "localname": "TitleOfIndividualAxis", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "srt_TitleOfIndividualWithRelationshipToEntityDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Title Of Individual With Relationship To Entity [Domain]", "terseLabel": "Title of Individual" } } }, "localname": "TitleOfIndividualWithRelationshipToEntityDomain", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "srt_WeightedAverageMember": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Weighted Average [Member]", "terseLabel": "Weighted Average [Member]" } } }, "localname": "WeightedAverageMember", "nsuri": "http://fasb.org/srt/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "stpr_CA": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "CALIFORNIA", "terseLabel": "California [Member]" } } }, "localname": "CA", "nsuri": "http://xbrl.sec.gov/stpr/2018-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "stpr_TX": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "TEXAS", "terseLabel": "Texas [Member]" } } }, "localname": "TX", "nsuri": "http://xbrl.sec.gov/stpr/2018-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_AccountingPoliciesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "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 Update201409 [Member]", "terseLabel": "ASU No. 2014-09 [Member]", "verboseLabel": "ASU No. 2014-09 [Member]" } } }, "localname": "AccountingStandardsUpdate201409Member", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail" ], "xbrltype": "domainItemType" }, "us-gaap_AccountingStandardsUpdate201602Member": { "auth_ref": [ "r409" ], "lang": { "en-US": { "role": { "documentation": "Accounting Standards Update 2016-02 Leases (Topic 842).", "label": "Accounting Standards Update201602 [Member]", "terseLabel": "ASU 2016-02" } } }, "localname": "AccountingStandardsUpdate201602Member", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_AccountsAndOtherReceivablesNetCurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10320.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, after allowance, receivable from customers, clients, or other third-parties, and receivables classified as other due within one year or the normal operating cycle, if longer.", "label": "Accounts And Other Receivables Net Current", "terseLabel": "Receivables, net" } } }, "localname": "AccountsAndOtherReceivablesNetCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "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 And Loans Receivable [Line Items]", "terseLabel": "Accounts Notes And Loans Receivable [Line Items]" } } }, "localname": "AccountsNotesAndLoansReceivableLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail" ], "xbrltype": "stringItemType" }, "us-gaap_AccountsPayableAndAccruedLiabilitiesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Primary financial statement caption encompassing accounts payable and accrued liabilities.", "label": "Accounts Payable And Accrued Liabilities [Member]", "terseLabel": "Accounts Payable, Accrued and Other Liabilities [Member]" } } }, "localname": "AccountsPayableAndAccruedLiabilitiesMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10180.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liabilities incurred to vendors for goods and services received, and accrued liabilities classified as other, payable within one year or the normal operating cycle, if longer.", "label": "Accounts Payable And Other Accrued Liabilities Current", "terseLabel": "Current portion of accounts payable, accrued expenses and other liabilities (see Note 29)", "totalLabel": "Total" } } }, "localname": "AccountsPayableAndOtherAccruedLiabilitiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccountsPayableRelatedPartiesCurrent": { "auth_ref": [ "r32", "r120", "r429", "r431", "r432" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10200.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).", "label": "Accounts Payable Related Parties Current", "terseLabel": "Current portion of payables to related parties" } } }, "localname": "AccountsPayableRelatedPartiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccountsReceivableRelatedParties": { "auth_ref": [ "r20", "r114", "r428", "r431", "r432", "r506" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10330.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "For an unclassified balance sheet, amount of receivables arising from transactions with related parties.", "label": "Accounts Receivable Related Parties", "terseLabel": "Receivables from related parties" } } }, "localname": "AccountsReceivableRelatedParties", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccruedPayrollTaxesCurrent": { "auth_ref": [ "r9", "r37" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": 10040.0, "parentTag": "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying value as of the balance sheet date of obligations incurred and payable for statutory payroll taxes incurred through that date and withheld from employees pertaining to services received from them, including entity's matching share of the employees FICA taxes and contributions to the state and federal unemployment insurance programs. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).", "label": "Accrued Payroll Taxes Current", "terseLabel": "Payroll taxes payable" } } }, "localname": "AccruedPayrollTaxesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment": { "auth_ref": [ "r30", "r216" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail": { "order": 10020.0, "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", "negatedLabel": "Accumulated depreciation and amortization" } } }, "localname": "AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife": { "auth_ref": [ "r203" ], "lang": { "en-US": { "role": { "documentation": "Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.", "label": "Acquired Finite Lived Intangible Assets Weighted Average Useful Life", "terseLabel": "Definite life, Weighted- Average Remaining Life (Years)" } } }, "localname": "AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "durationItemType" }, "us-gaap_AdditionalPaidInCapitalCommonStock": { "auth_ref": [ "r22" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10090.0, "parentTag": "us-gaap_StockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Value received from shareholders in common stock-related transactions that are in excess of par value or stated value and amounts received from other stock-related transactions. Includes only common stock transactions (excludes preferred stock transactions). May be called contributed capital, capital in excess of par, capital surplus, or paid-in capital.", "label": "Additional Paid In Capital Common Stock", "terseLabel": "Additional paid-in capital" } } }, "localname": "AdditionalPaidInCapitalCommonStock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "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 [Member]" } } }, "localname": "AdditionalPaidInCapitalMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "domainItemType" }, "us-gaap_AdjustmentForAmortization": { "auth_ref": [ "r104", "r209" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10380.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.", "label": "Adjustment For Amortization", "terseLabel": "Employee loan amortization" } } }, "localname": "AdjustmentForAmortization", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_AdjustmentsForNewAccountingPronouncementsAxis": { "auth_ref": [ "r123" ], "lang": { "en-US": { "role": { "documentation": "Information by new accounting pronouncement.", "label": "Adjustments For New Accounting Pronouncements [Axis]", "terseLabel": "Adjustments for New Accounting Pronouncements" } } }, "localname": "AdjustmentsForNewAccountingPronouncementsAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail" ], "xbrltype": "stringItemType" }, "us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts": { "auth_ref": [ "r243", "r253" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.", "label": "Adjustments To Additional Paid In Capital Stock Issued Issuance Costs", "terseLabel": "Contingent Class A common stock to be issued to newly acquired entities" } } }, "localname": "AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "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 income to net cash (used in) provided by operating activities:" } } }, "localname": "AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_AllocatedShareBasedCompensationExpense": { "auth_ref": [ "r278", "r297", "r300" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.", "label": "Allocated Share Based Compensation Expense", "terseLabel": "Compensation expense (benefit) related to limited partnership units" } } }, "localname": "AllocatedShareBasedCompensationExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_AlternativeInvestment": { "auth_ref": [ "r370", "r385" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.", "label": "Alternative Investment", "terseLabel": "Alternative investment" } } }, "localname": "AlternativeInvestment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_AmortizationOfFinancingCosts": { "auth_ref": [ "r74", "r104", "r402" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of amortization expense attributable to debt issuance costs.", "label": "Amortization Of Financing Costs", "verboseLabel": "Amortization of debt issuance costs" } } }, "localname": "AmortizationOfFinancingCosts", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_AmortizationOfIntangibleAssets": { "auth_ref": [ "r104", "r201", "r209" ], "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": "Intangible amortization expense" } } }, "localname": "AmortizationOfIntangibleAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_AncillaryFeeIncomeGeneratedByServicingFinancialAssetsAmount": { "auth_ref": [ "r449" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail": { "order": 10030.0, "parentTag": "nmrk_ContractuallySpecifiedServicingFeesAncillaryFeesEscrowInterestAndPlacementFeesEarnedInExchangeForServicingFinancialAssets", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "All amounts that are due to the servicer of a financial asset, excluding contractually specified servicing fees and late fees.", "label": "Ancillary Fee Income Generated By Servicing Financial Assets Amount", "terseLabel": "Ancillary fees" } } }, "localname": "AncillaryFeeIncomeGeneratedByServicingFinancialAssetsAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount": { "auth_ref": [ "r135" ], "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 computation of fully diluted earnings per share amount" } } }, "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis": { "auth_ref": [ "r135" ], "lang": { "en-US": { "role": { "documentation": "Information by type of antidilutive security.", "label": "Antidilutive Securities Excluded From Computation Of Earnings Per Share By Antidilutive Securities [Axis]", "terseLabel": "Antidilutive Securities" } } }, "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]", "terseLabel": "Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]" } } }, "localname": "AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_AntidilutiveSecuritiesNameDomain": { "auth_ref": [ "r135" ], "lang": { "en-US": { "role": { "documentation": "Incremental common shares attributable to securities that were not included in diluted earnings per share (EPS) because to do so would increase EPS amounts or decrease loss per share amounts for the period presented.", "label": "Antidilutive Securities Name [Domain]", "terseLabel": "Antidilutive Securities, Name" } } }, "localname": "AntidilutiveSecuritiesNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_ArrangementsAndNonarrangementTransactionsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Collaborative arrangement and arrangement other than collaborative applicable to revenue-generating activity or operations.", "label": "Arrangements And Nonarrangement Transactions [Member]", "terseLabel": "Collaborative Arrangement and Arrangement Other than Collaborative" } } }, "localname": "ArrangementsAndNonarrangementTransactionsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_Assets": { "auth_ref": [ "r151", "r477", "r502" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "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", "terseLabel": "Assets", "totalLabel": "Total assets" } } }, "localname": "Assets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_AssetsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Assets [Abstract]", "terseLabel": "Assets:" } } }, "localname": "AssetsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_AssetsCurrent": { "auth_ref": [ "r6", "r8", "r57" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10210.0, "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.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "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.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_AssetsFairValueDisclosure": { "auth_ref": [ "r371" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "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", "totalLabel": "Total" } } }, "localname": "AssetsFairValueDisclosure", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_AwardTypeAxis": { "auth_ref": [ "r279", "r299" ], "lang": { "en-US": { "role": { "documentation": "Information by type of award under share-based payment arrangement.", "label": "Award Type [Axis]", "terseLabel": "Award Type" } } }, "localname": "AwardTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail" ], "xbrltype": "stringItemType" }, "us-gaap_BalanceSheetLocationAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by location on balance sheet (statement of financial position).", "label": "Balance Sheet Location [Axis]", "terseLabel": "Balance Sheet Location" } } }, "localname": "BalanceSheetLocationAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_BalanceSheetLocationDomain": { "auth_ref": [ "r356", "r361" ], "lang": { "en-US": { "role": { "documentation": "Location in the balance sheet (statement of financial position).", "label": "Balance Sheet Location [Domain]", "terseLabel": "Balance Sheet Location" } } }, "localname": "BalanceSheetLocationDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "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.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationPolicies" ], "xbrltype": "textBlockItemType" }, "us-gaap_BelowMarketLeaseAccumulatedAmortization": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail": { "order": 11080.0, "parentTag": "us-gaap_BelowMarketLeaseNet", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of accumulated amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.", "label": "Below Market Lease Accumulated Amortization", "negatedLabel": "Below market leases, Accumulated Amortization" } } }, "localname": "BelowMarketLeaseAccumulatedAmortization", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BelowMarketLeaseGross": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail": { "order": 11070.0, "parentTag": "us-gaap_BelowMarketLeaseNet", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount before amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.", "label": "Below Market Lease Gross", "terseLabel": "Below market leases, Gross Amount" } } }, "localname": "BelowMarketLeaseGross", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BelowMarketLeaseNet": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount after amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.", "label": "Below Market Lease Net", "totalLabel": "Below market leases, Net Carrying Amount" } } }, "localname": "BelowMarketLeaseNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BrokersAndDealersDisclosureTextBlock": { "auth_ref": [ "r476" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for financial services, specifically for brokers and dealers, for the accounting period and at the balance sheet date. Disclosure may include amounts receivable from and payable to broker-dealers and clearing organizations, including securities failed to receive, deposits received for securities loaned, amounts payable to clearing organizations related to open transactions, floor brokerage payables and payables for commodities futures accounts liquidating to an equity balance on a broker-dealer's records. May also include disclosure on company's consolidation policy and a note indicating the amount of the broker-dealer's actual net capital and the amount of required net capital.", "label": "Brokers And Dealers Disclosure [Text Block]", "terseLabel": "Capital and Liquidity Requirements" } } }, "localname": "BrokersAndDealersDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirements" ], "xbrltype": "textBlockItemType" }, "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" } } }, "localname": "BusinessAcquisitionAcquireeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_BusinessAcquisitionAxis": { "auth_ref": [ "r316", "r317" ], "lang": { "en-US": { "role": { "documentation": "Information by business combination or series of individually immaterial business combinations.", "label": "Business Acquisition [Axis]", "terseLabel": "Business Acquisition" } } }, "localname": "BusinessAcquisitionAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_BusinessAcquisitionDateOfAcquisitionAgreement1": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Date when the business acquisition agreement was executed, in CCYY-MM-DD format.", "label": "Business Acquisition Date Of Acquisition Agreement1", "terseLabel": "Business acquisition, transaction agreement date" } } }, "localname": "BusinessAcquisitionDateOfAcquisitionAgreement1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition1": { "auth_ref": [ "r311", "r312", "r313" ], "lang": { "en-US": { "role": { "documentation": "Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.", "label": "Business Acquisition Effective Date Of Acquisition1", "terseLabel": "Business acquisition date" } } }, "localname": "BusinessAcquisitionEffectiveDateOfAcquisition1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "us-gaap_BusinessAcquisitionEquityInterestIssuedOrIssuableValueAssigned": { "auth_ref": [ "r332" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.", "label": "Business Acquisition Equity Interest Issued Or Issuable Value Assigned", "terseLabel": "Business acquisition, contingent non cash consideration, fair value" } } }, "localname": "BusinessAcquisitionEquityInterestIssuedOrIssuableValueAssigned", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued": { "auth_ref": [ "r332" ], "lang": { "en-US": { "role": { "documentation": "Number of shares of equity interests issued or issuable to acquire entity.", "label": "Business Acquisition Equity Interests Issued Or Issuable Number Of Shares Issued", "positiveVerboseLabel": "Business acquisition price paid (Partnership Units)" } } }, "localname": "BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_BusinessAcquisitionLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Business Acquisition [Line Items]", "terseLabel": "Business Acquisition [Line Items]" } } }, "localname": "BusinessAcquisitionLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "stringItemType" }, "us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired": { "auth_ref": [ "r314" ], "lang": { "en-US": { "role": { "documentation": "Percentage of voting equity interests acquired at the acquisition date in the business combination.", "label": "Business Acquisition Percentage Of Voting Interests Acquired", "terseLabel": "Ownership percentage acquired" } } }, "localname": "BusinessAcquisitionPercentageOfVotingInterestsAcquired", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount": { "auth_ref": [ "r334" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.", "label": "Business Acquisition Purchase Price Allocation Goodwill Expected Tax Deductible Amount", "terseLabel": "Business acquisition, amount deductible for tax" } } }, "localname": "BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue": { "auth_ref": [ "r320" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10030.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.", "label": "Business Combination Acquisition Of Less Than100 Percent Noncontrolling Interest Fair Value", "terseLabel": "Noncontrolling interest" } } }, "localname": "BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationConsiderationTransferred1": { "auth_ref": [ "r328", "r329", "r331" ], "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 Transferred1", "terseLabel": "Total consideration transferred" } } }, "localname": "BusinessCombinationConsiderationTransferred1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable": { "auth_ref": [ "r328", "r329" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.", "label": "Business Combination Consideration Transferred Equity Interests Issued And Issuable", "terseLabel": "Business acquisition price paid in units" } } }, "localname": "BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1": { "auth_ref": [ "r103", "r335" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10400.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.", "label": "Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1", "terseLabel": "Change in fair value of contingent consideration" } } }, "localname": "BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh": { "auth_ref": [ "r333" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.", "label": "Business Combination Contingent Consideration Arrangements Range Of Outcomes Value High", "terseLabel": "Undiscounted value of payments, assuming that all contingencies are met" } } }, "localname": "BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent": { "auth_ref": [ "r327", "r330" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": 10080.0, "parentTag": "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.", "label": "Business Combination Contingent Consideration Liability Current", "terseLabel": "Contingent consideration" } } }, "localname": "BusinessCombinationContingentConsiderationLiabilityCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationContingentConsiderationLiabilityMeasurementInput": { "auth_ref": [ "r376" ], "lang": { "en-US": { "role": { "documentation": "Value of input used to measure contingent consideration liability from business combination.", "label": "Business Combination Contingent Consideration Liability Measurement Input", "terseLabel": "Unobservable Inputs" } } }, "localname": "BusinessCombinationContingentConsiderationLiabilityMeasurementInput", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "decimalItemType" }, "us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent": { "auth_ref": [ "r327", "r330" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail": { "order": 10040.0, "parentTag": "us-gaap_OtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.", "label": "Business Combination Contingent Consideration Liability Noncurrent", "terseLabel": "Business acquisition, contingent cash consideration" } } }, "localname": "BusinessCombinationContingentConsiderationLiabilityNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationDisclosureTextBlock": { "auth_ref": [ "r336" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).", "label": "Business Combination Disclosure [Text Block]", "terseLabel": "Acquisitions" } } }, "localname": "BusinessCombinationDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitions" ], "xbrltype": "textBlockItemType" }, "us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual": { "auth_ref": [ "r315" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.", "label": "Business Combination Pro Forma Information Revenue Of Acquiree Since Acquisition Date Actual", "terseLabel": "Business acquisition, aggregate revenue contribution" } } }, "localname": "BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets": { "auth_ref": [ "r319" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10010.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of assets acquired at the acquisition date.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets", "totalLabel": "Total assets" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets [Abstract]", "terseLabel": "Assets" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "stringItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents": { "auth_ref": [ "r319" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10060.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents", "terseLabel": "Cash and cash equivalents" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables": { "auth_ref": [ "r319" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10080.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Receivables", "terseLabel": "Receivables, net" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities [Abstract]", "terseLabel": "Current liabilities" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "stringItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable": { "auth_ref": [ "r319" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10040.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Accounts Payable", "terseLabel": "Current portion of accounts payable, accrued expenses and other liabilities" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill": { "auth_ref": [ "r319" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10100.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of intangible assets, excluding goodwill, acquired at the acquisition date.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangible Assets Other Than Goodwill", "terseLabel": "Other intangible assets, net" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities": { "auth_ref": [ "r319" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10020.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of liabilities assumed at the acquisition date.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Liabilities", "totalLabel": "Total liabilities" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment": { "auth_ref": [ "r318", "r319" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10090.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of property, plant, and equipment recognized as of the acquisition date.", "label": "Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Property Plant And Equipment", "terseLabel": "Fixed Assets, net" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedLessNoncontrollingInterest": { "auth_ref": [ "r319" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.", "label": "Business Combination Recognized Identifiable Assets Acquired Goodwill And Liabilities Assumed Less Noncontrolling Interest", "verboseLabel": "Net assets exceeded" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedLessNoncontrollingInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet": { "auth_ref": [ "r319" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.", "label": "Business Combination Recognized Identifiable Assets Acquired Goodwill And Liabilities Assumed Net", "totalLabel": "Net assets acquired" } } }, "localname": "BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_BusinessCombinationsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Business Combinations [Abstract]" } } }, "localname": "BusinessCombinationsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_CapitalUnitClassDomain": { "auth_ref": [ "r524" ], "lang": { "en-US": { "role": { "documentation": "Description of the type or class of capital units or capital shares.", "label": "Capital Unit Class [Domain]", "terseLabel": "Capital Unit, Class" } } }, "localname": "CapitalUnitClassDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_CapitalUnitsByClassAxis": { "auth_ref": [ "r522", "r525" ], "lang": { "en-US": { "role": { "documentation": "Information by type or class of the entity's capital units.", "label": "Capital Units By Class [Axis]", "terseLabel": "Capital Units by Class" } } }, "localname": "CapitalUnitsByClassAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_CapitalizedComputerSoftwareAdditions": { "auth_ref": [ "r202" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Additions made to capitalized computer software costs during the period.", "label": "Capitalized Computer Software Additions", "terseLabel": "Software development costs capitalized" } } }, "localname": "CapitalizedComputerSoftwareAdditions", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_CapitalizedComputerSoftwareAmortization1": { "auth_ref": [ "r536", "r537" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of expense for amortization of capitalized computer software costs.", "label": "Capitalized Computer Software Amortization1", "terseLabel": "Amortization of software development costs" } } }, "localname": "CapitalizedComputerSoftwareAmortization1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_CarryingReportedAmountFairValueDisclosureMember": { "auth_ref": [ "r389", "r390" ], "lang": { "en-US": { "role": { "documentation": "Measured as reported on the statement of financial position (balance sheet).", "label": "Carrying Reported Amount Fair Value Disclosure [Member]", "verboseLabel": "Cost Basis [Member]" } } }, "localname": "CarryingReportedAmountFairValueDisclosureMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail" ], "xbrltype": "domainItemType" }, "us-gaap_CashAndCashEquivalentsAtCarryingValue": { "auth_ref": [ "r1", "r27", "r106" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10280.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.", "label": "Cash And Cash Equivalents At Carrying Value", "terseLabel": "Cash and cash equivalents" } } }, "localname": "CashAndCashEquivalentsAtCarryingValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations": { "auth_ref": [ "r97", "r106", "r111" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including, but not limited to, 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 Including Disposal Group And Discontinued Operations", "periodEndLabel": "Cash and cash equivalents and restricted cash at end of period", "periodStartLabel": "Cash and cash equivalents and restricted cash at beginning of period" } } }, "localname": "CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect": { "auth_ref": [ "r97", "r399" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) in cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; excluding 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 Excluding Exchange Rate Effect", "totalLabel": "Net (decrease) increase in cash and cash equivalents and restricted cash" } } }, "localname": "CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "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" } } }, "localname": "ClassOfStockDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail", "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail" ], "xbrltype": "stringItemType" }, "us-gaap_CommitmentsAndContingencies": { "auth_ref": [ "r47", "r221", "r484", "r508" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10020.0, "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 (see Note 31)" } } }, "localname": "CommitmentsAndContingencies", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_CommitmentsAndContingenciesDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Commitments And Contingencies Disclosure [Abstract]" } } }, "localname": "CommitmentsAndContingenciesDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_CommitmentsAndContingenciesDisclosureTextBlock": { "auth_ref": [ "r220", "r228" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingencies" ], "xbrltype": "textBlockItemType" }, "us-gaap_CommonClassAMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Classification of common stock representing ownership interest in a corporation.", "label": "Common Class A [Member]", "terseLabel": "Class A Common Stock [Member]" } } }, "localname": "CommonClassAMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail", "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "domainItemType" }, "us-gaap_CommonClassBMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Classification of common stock that has different rights than Common Class A, representing ownership interest in a corporation.", "label": "Common Class B [Member]", "terseLabel": "Class B Common Stock [Member]" } } }, "localname": "CommonClassBMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "domainItemType" }, "us-gaap_CommonStockConversionFeatures": { "auth_ref": [ "r244", "r247", "r248", "r249" ], "lang": { "en-US": { "role": { "documentation": "Description of common stock conversion feature. Includes, but is not limited to, conversion price; conversion right; timing of right; terms, event or change in circumstance causing contingency to be met or adjustment to conversion price or number of shares; manner of settlement upon conversion; and method of settlement.", "label": "Common Stock Conversion Features", "terseLabel": "Common stock conversion features" } } }, "localname": "CommonStockConversionFeatures", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_CommonStockDividendsPerShareCashPaid": { "auth_ref": [ "r253" ], "lang": { "en-US": { "role": { "documentation": "Aggregate dividends paid during the period for each share of common stock outstanding.", "label": "Common Stock Dividends Per Share Cash Paid", "negatedLabel": "Dividends paid per share of common stock" } } }, "localname": "CommonStockDividendsPerShareCashPaid", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "perShareItemType" }, "us-gaap_CommonStockDividendsPerShareDeclared": { "auth_ref": [ "r253" ], "lang": { "en-US": { "role": { "documentation": "Aggregate dividends declared during the period for each share of common stock outstanding.", "label": "Common Stock Dividends Per Share Declared", "negatedLabel": "Dividends declared per share of common stock", "verboseLabel": "Common stock dividends per share declared" } } }, "localname": "CommonStockDividendsPerShareDeclared", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "perShareItemType" }, "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.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "domainItemType" }, "us-gaap_CommonStockParOrStatedValuePerShare": { "auth_ref": [ "r19" ], "lang": { "en-US": { "role": { "documentation": "Face amount or stated value per share of common stock.", "label": "Common Stock Par Or Stated Value Per Share", "terseLabel": "Common stock, par value" } } }, "localname": "CommonStockParOrStatedValuePerShare", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical" ], "xbrltype": "perShareItemType" }, "us-gaap_CommonStockSharesAuthorized": { "auth_ref": [ "r19" ], "lang": { "en-US": { "role": { "documentation": "The maximum number of common shares permitted to be issued by an entity's charter and bylaws.", "label": "Common Stock Shares Authorized", "terseLabel": "Common stock, shares authorized" } } }, "localname": "CommonStockSharesAuthorized", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical" ], "xbrltype": "sharesItemType" }, "us-gaap_CommonStockSharesIssued": { "auth_ref": [ "r19" ], "lang": { "en-US": { "role": { "documentation": "Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.", "label": "Common Stock Shares Issued", "terseLabel": "Common stock, shares issued" } } }, "localname": "CommonStockSharesIssued", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical" ], "xbrltype": "sharesItemType" }, "us-gaap_CommonStockSharesOutstanding": { "auth_ref": [ "r19", "r243" ], "lang": { "en-US": { "role": { "documentation": "Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.", "label": "Common Stock Shares Outstanding", "periodEndLabel": "Shares outstanding at end of period", "periodStartLabel": "Shares outstanding at beginning of period", "terseLabel": "Common stock, shares outstanding" } } }, "localname": "CommonStockSharesOutstanding", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical" ], "xbrltype": "sharesItemType" }, "us-gaap_CommonStockValue": { "auth_ref": [ "r19" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10070.0, "parentTag": "us-gaap_StockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.", "label": "Common Stock Value", "terseLabel": "Common stock value" } } }, "localname": "CommonStockValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_CommonStockVotingRights": { "auth_ref": [ "r244" ], "lang": { "en-US": { "role": { "documentation": "Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.", "label": "Common Stock Voting Rights", "terseLabel": "Common stock voting rights description" } } }, "localname": "CommonStockVotingRights", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_CommonUnitIssued": { "auth_ref": [ "r140", "r141", "r253" ], "lang": { "en-US": { "role": { "documentation": "Number of common units issued of limited liability company (LLC).", "label": "Common Unit Issued", "terseLabel": "Common stock units issued" } } }, "localname": "CommonUnitIssued", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_CompensationRelatedCostsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Compensation Related Costs [Abstract]" } } }, "localname": "CompensationRelatedCostsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems": { "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": "Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]", "terseLabel": "Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]" } } }, "localname": "ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ComprehensiveIncomeNetOfTax": { "auth_ref": [ "r63", "r65", "r66" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome": { "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 Net Of Tax", "totalLabel": "Comprehensive income available to common stockholders" } } }, "localname": "ComprehensiveIncomeNetOfTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest": { "auth_ref": [ "r63", "r65", "r341", "r342", "r350" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome": { "order": 10020.0, "parentTag": "us-gaap_ComprehensiveIncomeNetOfTax", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.", "label": "Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest", "terseLabel": "Less: Comprehensive income attributable to noncontrolling interests, net of tax" } } }, "localname": "ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest": { "auth_ref": [ "r63", "r65", "r340", "r350" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome": { "order": 10010.0, "parentTag": "us-gaap_ComprehensiveIncomeNetOfTax", "weight": 1.0 } }, "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. Excludes changes in equity resulting from investments by owners and distributions to owners.", "label": "Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest", "totalLabel": "Comprehensive income, net of tax" } } }, "localname": "ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome" ], "xbrltype": "monetaryItemType" }, "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 Communications Equipment [Member]" } } }, "localname": "ComputerEquipmentMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "xbrltype": "domainItemType" }, "us-gaap_ConcentrationRiskBenchmarkDomain": { "auth_ref": [ "r143", "r144", "r391", "r392" ], "lang": { "en-US": { "role": { "documentation": "The denominator in a calculation of a disclosed concentration risk percentage.", "label": "Concentration Risk Benchmark [Domain]", "terseLabel": "Concentration Risk Benchmark" } } }, "localname": "ConcentrationRiskBenchmarkDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_ConcentrationRiskByBenchmarkAxis": { "auth_ref": [ "r143", "r144", "r391", "r392", "r521" ], "lang": { "en-US": { "role": { "documentation": "Information by benchmark of concentration risk.", "label": "Concentration Risk By Benchmark [Axis]", "terseLabel": "Concentration Risk Benchmark" } } }, "localname": "ConcentrationRiskByBenchmarkAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ConcentrationRiskByTypeAxis": { "auth_ref": [ "r143", "r144", "r391", "r392", "r521" ], "lang": { "en-US": { "role": { "documentation": "Information by type of concentration risk, for example, but not limited to, asset, liability, net assets, geographic, customer, employees, supplier, lender.", "label": "Concentration Risk By Type [Axis]", "terseLabel": "Concentration Risk Type" } } }, "localname": "ConcentrationRiskByTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure": { "auth_ref": [ "r393" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity.", "label": "Concentration Risk Credit Risk Financial Instrument Maximum Exposure", "terseLabel": "Maximum pre-credit enhancement loss exposure" } } }, "localname": "ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ConcentrationRiskDisclosureTextBlock": { "auth_ref": [ "r146" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.", "label": "Concentration Risk Disclosure [Text Block]", "terseLabel": "Concentrations of Credit Risk" } } }, "localname": "ConcentrationRiskDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRisk" ], "xbrltype": "textBlockItemType" }, "us-gaap_ConcentrationRiskLineItems": { "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": "Concentration Risk [Line Items]", "terseLabel": "Concentration Risk [Line Items]" } } }, "localname": "ConcentrationRiskLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ConcentrationRiskPercentage1": { "auth_ref": [ "r143", "r144", "r391", "r392" ], "lang": { "en-US": { "role": { "documentation": "For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the \"benchmark\" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.", "label": "Concentration Risk Percentage1", "terseLabel": "Concentration risk percentage" } } }, "localname": "ConcentrationRiskPercentage1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "us-gaap_ConcentrationRiskTable": { "auth_ref": [ "r142", "r143", "r144", "r145", "r391", "r394" ], "lang": { "en-US": { "role": { "documentation": "Describes the nature of a concentration, a benchmark to which it is compared, and the percentage that the risk is to the benchmark.", "label": "Concentration Risk [Table]", "terseLabel": "Concentration Risk [Table]" } } }, "localname": "ConcentrationRiskTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ConcentrationRiskTypeDomain": { "auth_ref": [ "r143", "r144", "r391", "r392" ], "lang": { "en-US": { "role": { "documentation": "For an entity that discloses a concentration risk as a percentage of some financial balance or benchmark, identifies the type (for example, asset, liability, net assets, geographic, customer, employees, supplier, lender) of the concentration.", "label": "Concentration Risk Type [Domain]", "terseLabel": "Concentration Risk Type" } } }, "localname": "ConcentrationRiskTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_ConstructionLoansMember": { "auth_ref": [ "r533" ], "lang": { "en-US": { "role": { "documentation": "A borrowing arrangement which provides the entity constructing a facility (such as a building and a landfill) with funds to effect construction, generally on a draw down, or as needed, basis.", "label": "Construction Loans [Member]", "terseLabel": "Construction Loans [Member]" } } }, "localname": "ConstructionLoansMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "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" } } }, "localname": "ContingentConsiderationByTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "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" } } }, "localname": "ContingentConsiderationTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_ContractWithCustomerLiabilityNoncurrent": { "auth_ref": [ "r260", "r261", "r264" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.", "label": "Contract With Customer Liability Noncurrent", "terseLabel": "Deferred revenue" } } }, "localname": "ContractWithCustomerLiabilityNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ContractWithCustomerLiabilityRevenueRecognized": { "auth_ref": [ "r265" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.", "label": "Contract With Customer Liability Revenue Recognized", "terseLabel": "Deferred revenue, revenue recognized" } } }, "localname": "ContractWithCustomerLiabilityRevenueRecognized", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ContractualObligation": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.", "label": "Contractual Obligation", "terseLabel": "Total remaining draws on construction loans committed to fund" } } }, "localname": "ContractualObligation", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ContractuallySpecifiedServicingFeesAmount": { "auth_ref": [ "r449" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail": { "order": 10010.0, "parentTag": "nmrk_ContractuallySpecifiedServicingFeesAncillaryFeesEscrowInterestAndPlacementFeesEarnedInExchangeForServicingFinancialAssets", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.", "label": "Contractually Specified Servicing Fees Amount", "terseLabel": "Servicing fees" } } }, "localname": "ContractuallySpecifiedServicingFeesAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsComponentsOfServicingFeesIncludedInManagementServicesServicingFeesAndOtherDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ConversionOfStockSharesConverted1": { "auth_ref": [ "r108", "r109", "r110" ], "lang": { "en-US": { "role": { "documentation": "The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. \"Part noncash\" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.", "label": "Conversion Of Stock Shares Converted1", "terseLabel": "Conversion of Stock, Shares Converted" } } }, "localname": "ConversionOfStockSharesConverted1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_CostDirectLabor": { "auth_ref": [ "r75" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10140.0, "parentTag": "nmrk_CompensationAndEmployeeBenefitsNet", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Cost of labor directly related to good produced and service rendered. Includes, but is not limited to, payroll cost and equity-based compensation.", "label": "Cost Direct Labor", "terseLabel": "Compensation and employee benefits" } } }, "localname": "CostDirectLabor", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_CostsAndExpenses": { "auth_ref": [ "r76" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10080.0, "parentTag": "us-gaap_OperatingIncomeLoss", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Total costs of sales and operating expenses for the period.", "label": "Costs And Expenses", "totalLabel": "Total operating expenses" } } }, "localname": "CostsAndExpenses", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_CostsAndExpensesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Costs And Expenses [Abstract]", "terseLabel": "Expenses:" } } }, "localname": "CostsAndExpensesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "stringItemType" }, "us-gaap_CreditConcentrationRiskMember": { "auth_ref": [ "r394" ], "lang": { "en-US": { "role": { "documentation": "Reflects the percentage that a specified receivable or amount at risk from a counterparty under a contractual arrangement is to a specified benchmark, such as total receivables, net revenues, pretax results. Risk is the materially adverse effects of loss attributable to (a) the failure to collect a significant receivable from a major customer or group of homogeneous accounts, or (b) a failure by a counterparty to perform under terms of a contractual arrangement.", "label": "Credit Concentration Risk [Member]", "terseLabel": "Credit Concentration Risk [Member]" } } }, "localname": "CreditConcentrationRiskMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_CreditFacilityAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by type of credit facility. Credit facilities provide capital to borrowers without the need to structure a loan for each borrowing.", "label": "Credit Facility [Axis]", "terseLabel": "Credit Facility" } } }, "localname": "CreditFacilityAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "stringItemType" }, "us-gaap_CreditFacilityDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Type of credit facility. Credit facilities provide capital to borrowers without the need to structure a loan for each borrowing.", "label": "Credit Facility [Domain]", "terseLabel": "Credit Facility" } } }, "localname": "CreditFacilityDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "domainItemType" }, "us-gaap_CreditRiskMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The risk that a borrower will fail to pay interest or principal on a loan or debt security when due.", "label": "Credit Risk [Member]", "terseLabel": "Credit Risk [Member]" } } }, "localname": "CreditRiskMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_CustomerContractsMember": { "auth_ref": [ "r325" ], "lang": { "en-US": { "role": { "documentation": "Entity's established relationships with its customers through contracts.", "label": "Customer Contracts [Member]", "terseLabel": "Contractual Customers [Member]" } } }, "localname": "CustomerContractsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_CustomerRelatedIntangibleAssetsMember": { "auth_ref": [ "r322" ], "lang": { "en-US": { "role": { "documentation": "Customer-related asset, including, but not limited to, customer lists, and noncontractual customer relationships.", "label": "Customer Related Intangible Assets [Member]", "terseLabel": "Non-contractual Customers [Member]" } } }, "localname": "CustomerRelatedIntangibleAssetsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_DebtDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Debt Disclosure [Abstract]" } } }, "localname": "DebtDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_DebtDisclosureTextBlock": { "auth_ref": [ "r239" ], "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": "Long-Term Debt" } } }, "localname": "DebtDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebt" ], "xbrltype": "textBlockItemType" }, "us-gaap_DebtInstrumentAxis": { "auth_ref": [ "r14", "r15", "r16", "r478", "r479", "r501" ], "lang": { "en-US": { "role": { "documentation": "Information by type of debt instrument, including, but not limited to, draws against credit facilities.", "label": "Debt Instrument [Axis]", "terseLabel": "Debt Instrument" } } }, "localname": "DebtInstrumentAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "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 Rate1", "positiveTerseLabel": "Applicable margin", "terseLabel": "Interest rate", "verboseLabel": "Stated Spread to One Month LIBOR" } } }, "localname": "DebtInstrumentBasisSpreadOnVariableRate1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "percentItemType" }, "us-gaap_DebtInstrumentDateOfFirstRequiredPayment1": { "auth_ref": [ "r44", "r494" ], "lang": { "en-US": { "role": { "documentation": "Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.", "label": "Debt Instrument Date Of First Required Payment1", "terseLabel": "Debt instrument, date of first required payment" } } }, "localname": "DebtInstrumentDateOfFirstRequiredPayment1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "us-gaap_DebtInstrumentFaceAmount": { "auth_ref": [ "r401", "r404" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Face (par) amount of debt instrument at time of issuance.", "label": "Debt Instrument Face Amount", "verboseLabel": "Debt instrument face amount" } } }, "localname": "DebtInstrumentFaceAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DebtInstrumentFeeAmount": { "auth_ref": [ "r43" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of the fee that accompanies borrowing money under the debt instrument.", "label": "Debt Instrument Fee Amount", "terseLabel": "Debt instrument, underwriting fees paid to CF&Co" } } }, "localname": "DebtInstrumentFeeAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DebtInstrumentInterestRateStatedPercentage": { "auth_ref": [ "r39" ], "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", "verboseLabel": "Stated interest rate" } } }, "localname": "DebtInstrumentInterestRateStatedPercentage", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "us-gaap_DebtInstrumentInterestRateTerms": { "auth_ref": [ "r39" ], "lang": { "en-US": { "role": { "documentation": "Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.", "label": "Debt Instrument Interest Rate Terms", "terseLabel": "Interest rate terms" } } }, "localname": "DebtInstrumentInterestRateTerms", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DebtInstrumentIssuanceDate1": { "auth_ref": [ "r42" ], "lang": { "en-US": { "role": { "documentation": "Date the debt instrument was issued, in CCYY-MM-DD format.", "label": "Debt Instrument Issuance Date1", "terseLabel": "Debt instrument, issuance date" } } }, "localname": "DebtInstrumentIssuanceDate1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "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.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DebtInstrumentMaturityDate": { "auth_ref": [ "r40", "r376" ], "lang": { "en-US": { "role": { "documentation": "Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.", "label": "Debt Instrument Maturity Date", "terseLabel": "Maturity date" } } }, "localname": "DebtInstrumentMaturityDate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "dateItemType" }, "us-gaap_DebtInstrumentNameDomain": { "auth_ref": [ "r44" ], "lang": { "en-US": { "role": { "documentation": "The name for the particular debt instrument or borrowing that distinguishes it from other debt instruments or borrowings, including draws against credit facilities.", "label": "Debt Instrument Name [Domain]", "terseLabel": "Debt Instrument, Name" } } }, "localname": "DebtInstrumentNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "us-gaap_DebtInstrumentPaymentTerms": { "auth_ref": [ "r41", "r494" ], "lang": { "en-US": { "role": { "documentation": "Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.", "label": "Debt Instrument Payment Terms", "terseLabel": "Debt instrument, payment terms" } } }, "localname": "DebtInstrumentPaymentTerms", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DebtInstrumentTable": { "auth_ref": [ "r44", "r118", "r244", "r250", "r251", "r252", "r400", "r401", "r404", "r495" ], "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": "Debt Instrument [Table]", "terseLabel": "Debt Instrument [Table]" } } }, "localname": "DebtInstrumentTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DebtInstrumentUnamortizedDiscountPremiumNet": { "auth_ref": [ "r400", "r401", "r402", "r403", "r404" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, after accumulated amortization, of debt discount (premium).", "label": "Debt Instrument Unamortized Discount Premium Net", "terseLabel": "Debt discount" } } }, "localname": "DebtInstrumentUnamortizedDiscountPremiumNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense": { "auth_ref": [ "r271", "r278" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The compensation expense recognized during the period pertaining to the deferred compensation arrangement.", "label": "Deferred Compensation Arrangement With Individual Compensation Expense", "terseLabel": "Deferred cash compensation expense recognized" } } }, "localname": "DeferredCompensationArrangementWithIndividualCompensationExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredCompensationCashbasedArrangementsLiabilityCurrentAndNoncurrent": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements. Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.", "label": "Deferred Compensation Cashbased Arrangements Liability Current And Noncurrent", "terseLabel": "Liability for deferred cash compensation awards" } } }, "localname": "DeferredCompensationCashbasedArrangementsLiabilityCurrentAndNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredFinanceCostsNet": { "auth_ref": [ "r31", "r402" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.", "label": "Deferred Finance Costs Net", "terseLabel": "Debt issuance cost" } } }, "localname": "DeferredFinanceCostsNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredIncomeTaxExpenseBenefit": { "auth_ref": [ "r104", "r113", "r306", "r307" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10390.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.", "label": "Deferred Income Tax Expense Benefit", "terseLabel": "Deferred tax provision" } } }, "localname": "DeferredIncomeTaxExpenseBenefit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredRentCreditNoncurrent": { "auth_ref": [ "r48", "r406" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail": { "order": 10070.0, "parentTag": "us-gaap_OtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "For a classified balance sheet, the cumulative difference between the rental income or 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, by the lessor or lessee, respectively, more than one year after the balance sheet date.", "label": "Deferred Rent Credit Noncurrent", "terseLabel": "Deferred rent" } } }, "localname": "DeferredRentCreditNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DeferredTaxAssetsLiabilitiesNet": { "auth_ref": [ "r305" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail": { "order": 10020.0, "parentTag": "us-gaap_OtherAssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.", "label": "Deferred Tax Assets Liabilities Net", "terseLabel": "Deferred tax assets" } } }, "localname": "DeferredTaxAssetsLiabilitiesNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DepositAssets": { "auth_ref": [ "r56" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail": { "order": 10040.0, "parentTag": "us-gaap_OtherAssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.", "label": "Deposit Assets", "terseLabel": "Rent and other deposits" } } }, "localname": "DepositAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DepositAssetsDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Deposit Assets Disclosure [Abstract]" } } }, "localname": "DepositAssetsDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_Depreciation": { "auth_ref": [ "r104", "r214" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.", "label": "Depreciation", "terseLabel": "Depreciation expense" } } }, "localname": "Depreciation", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DepreciationAndAmortization": { "auth_ref": [ "r104", "r214" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10350.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": -1.0 }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10130.0, "parentTag": "us-gaap_CostsAndExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.", "label": "Depreciation And Amortization", "terseLabel": "Depreciation and amortization" } } }, "localname": "DepreciationAndAmortization", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeAssets": { "auth_ref": [ "r59", "r60", "r388" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail": { "order": 10050.0, "parentTag": "us-gaap_AssetsFairValueDisclosure", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.", "label": "Derivative Assets", "terseLabel": "Nasdaq Forwards" } } }, "localname": "DerivativeAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeAssetsCurrent": { "auth_ref": [ "r59" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail": { "order": 10010.0, "parentTag": "us-gaap_OtherAssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.", "label": "Derivative Assets Current", "terseLabel": "Derivative assets" } } }, "localname": "DerivativeAssetsCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeAssetsNoncurrent": { "auth_ref": [ "r59" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail": { "order": 10050.0, "parentTag": "us-gaap_OtherAssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.", "label": "Derivative Assets Noncurrent", "terseLabel": "Derivative assets" } } }, "localname": "DerivativeAssetsNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeContractTypeDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Financial instrument or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.", "label": "Derivative Contract Type [Domain]", "terseLabel": "Derivative Contract" } } }, "localname": "DerivativeContractTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_DerivativeGainLossOnDerivativeNet": { "auth_ref": [ "r358" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.", "label": "Derivative Gain Loss On Derivative Net", "terseLabel": "Gain (loss) recognized in income for derivatives", "verboseLabel": "Change in fair value of rate lock commitments, net" } } }, "localname": "DerivativeGainLossOnDerivativeNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeInstrumentRiskAxis": { "auth_ref": [ "r357", "r359", "r363", "r365" ], "lang": { "en-US": { "role": { "documentation": "Information by type of derivative contract.", "label": "Derivative Instrument Risk [Axis]", "terseLabel": "Derivative Instrument" } } }, "localname": "DerivativeInstrumentRiskAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Derivative Instruments And Hedging Activities Disclosure [Abstract]" } } }, "localname": "DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock": { "auth_ref": [ "r369" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.", "label": "Derivative Instruments And Hedging Activities Disclosure [Text Block]", "terseLabel": "Derivatives" } } }, "localname": "DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivatives" ], "xbrltype": "textBlockItemType" }, "us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable": { "auth_ref": [ "r355", "r357", "r363", "r365", "r366", "r367", "r368" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about the location and amount of derivative instruments and nonderivative instruments designated as hedging instruments reported before netting adjustments, and the amount of gain (loss) on derivative instruments and nonderivative instruments designated and qualified as hedging instruments.", "label": "Derivative Instruments Gain Loss By Hedging Relationship By Income Statement Location By Derivative Instrument Risk [Table]", "terseLabel": "Derivative Instruments Gain Loss By Hedging Relationship By Income Statement Location By Derivative Instrument Risk [Table]" } } }, "localname": "DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DerivativeInstrumentsGainLossLineItems": { "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": "Derivative Instruments Gain Loss [Line Items]", "terseLabel": "Derivative Instruments Gain Loss [Line Items]" } } }, "localname": "DerivativeInstrumentsGainLossLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue": { "auth_ref": [ "r360" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail": { "order": 10070.0, "parentTag": "us-gaap_AssetsFairValueDisclosure", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.", "label": "Derivative Instruments Not Designated As Hedging Instruments Asset At Fair Value", "terseLabel": "Derivative contract, Assets" } } }, "localname": "DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue": { "auth_ref": [ "r360" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail": { "order": 10020.0, "parentTag": "us-gaap_LiabilitiesFairValueDisclosure", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.", "label": "Derivative Instruments Not Designated As Hedging Instruments Liability At Fair Value", "terseLabel": "Derivative contract, Liabilities" } } }, "localname": "DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeLiabilitiesCurrent": { "auth_ref": [ "r59" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": 10060.0, "parentTag": "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.", "label": "Derivative Liabilities Current", "terseLabel": "Derivative liability" } } }, "localname": "DerivativeLiabilitiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DerivativeNotionalAmount": { "auth_ref": [ "r353", "r354" ], "lang": { "en-US": { "role": { "documentation": "Nominal or face amount used to calculate payment on derivative.", "label": "Derivative Notional Amount", "terseLabel": "Derivative contract, Notional Amounts" } } }, "localname": "DerivativeNotionalAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member": { "auth_ref": [ "r268" ], "lang": { "en-US": { "role": { "documentation": "Effect in current period from application of guidance for revenue from contract with customer compared with guidance for revenue recognition applicable prior to change when using transition method for cumulative effect in period including initial date of application.", "label": "Difference Between Revenue Guidance In Effect Before And After Topic606 [Member]", "terseLabel": "Impact of ASC 606 [Member]", "verboseLabel": "Impact of ASC 606 [Member]" } } }, "localname": "DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_DisaggregationOfRevenueLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Disaggregation Of Revenue [Line Items]", "terseLabel": "Disaggregation Of Revenue [Line Items]" } } }, "localname": "DisaggregationOfRevenueLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DisaggregationOfRevenueTable": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about disaggregation of revenue into categories depicting how nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factor.", "label": "Disaggregation Of Revenue [Table]", "terseLabel": "Disaggregation Of Revenue [Table]" } } }, "localname": "DisaggregationOfRevenueTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail" ], "xbrltype": "stringItemType" }, "us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock": { "auth_ref": [ "r302" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for share-based payment arrangement.", "label": "Disclosure Of Compensation Related Costs Share Based Payments [Text Block]", "terseLabel": "Compensation" } } }, "localname": "DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensation" ], "xbrltype": "textBlockItemType" }, "us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]" } } }, "localname": "DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Name of disposal group.", "label": "Disposal Groups Including Discontinued Operations Name [Domain]", "terseLabel": "Disposal Group Name" } } }, "localname": "DisposalGroupsIncludingDiscontinuedOperationsNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_DistributionMadeToLimitedLiabilityCompanyLLCMemberUnitDistribution": { "auth_ref": [ "r140", "r141", "r253" ], "lang": { "en-US": { "role": { "documentation": "Number of units distributed for payment of a unit distribution to unit-holder of a limited liability company (LLC).", "label": "Distribution Made To Limited Liability Company L L C Member Unit Distribution", "terseLabel": "Limited partnership interests units" } } }, "localname": "DistributionMadeToLimitedLiabilityCompanyLLCMemberUnitDistribution", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_DistributionMadeToLimitedPartnerCashDistributionsDeclared": { "auth_ref": [ "r140", "r141", "r253" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of equity impact of cash distribution declared to unit-holder of limited partnership (LP).", "label": "Distribution Made To Limited Partner Cash Distributions Declared", "terseLabel": "Income allocated to limited partnership units" } } }, "localname": "DistributionMadeToLimitedPartnerCashDistributionsDeclared", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_DistributionMadeToLimitedPartnerUnitDistribution": { "auth_ref": [ "r140", "r141", "r253" ], "lang": { "en-US": { "role": { "documentation": "Number of units distributed for payment of a unit distribution to unit-holder of limited partnership (LP).", "label": "Distribution Made To Limited Partner Unit Distribution", "terseLabel": "Aggregate distribution of shares in spin-off" } } }, "localname": "DistributionMadeToLimitedPartnerUnitDistribution", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_DividendPayableDateToBePaidDayMonthAndYear": { "auth_ref": [ "r108" ], "lang": { "en-US": { "role": { "documentation": "Date the declared dividend will be paid, in CCYY-MM-DD format.", "label": "Dividend Payable Date To Be Paid Day Month And Year", "terseLabel": "Dividend payable date" } } }, "localname": "DividendPayableDateToBePaidDayMonthAndYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "us-gaap_DividendsCommonStockStock": { "auth_ref": [ "r253" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of paid and unpaid common stock dividends declared with the form of settlement in stock.", "label": "Dividends Common Stock Stock", "negatedLabel": "Dividends to common stockholders" } } }, "localname": "DividendsCommonStockStock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_DividendsPayableDateDeclaredDayMonthAndYear": { "auth_ref": [ "r108" ], "lang": { "en-US": { "role": { "documentation": "Date the dividend to be paid was declared, in CCYY-MM-DD format.", "label": "Dividends Payable Date Declared Day Month And Year", "terseLabel": "Dividends payable date declared" } } }, "localname": "DividendsPayableDateDeclaredDayMonthAndYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "us-gaap_DividendsPayableDateOfRecordDayMonthAndYear": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.", "label": "Dividends Payable Date Of Record Day Month And Year", "terseLabel": "Dividends payable date of record" } } }, "localname": "DividendsPayableDateOfRecordDayMonthAndYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail" ], "xbrltype": "dateItemType" }, "us-gaap_DividendsPreferredStock": { "auth_ref": [ "r253", "r493" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).", "label": "Dividends Preferred Stock", "negatedLabel": "Preferred dividend on exchangeable preferred partnership units" } } }, "localname": "DividendsPreferredStock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_DueFromEmployeesNoncurrent": { "auth_ref": [ "r11", "r21", "r114", "r428", "r430" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10240.0, "parentTag": "us-gaap_Assets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amounts due from an Entity employee, not to include stockholders or officers, which are usually due after 1 year (or 1 business cycle).", "label": "Due From Employees Noncurrent", "terseLabel": "Loans, forgivable loans and other receivables from employees and partners, net", "verboseLabel": "Loans, forgivable loans and other receivables from employees and partners" } } }, "localname": "DueFromEmployeesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_DueFromRelatedPartiesCurrent": { "auth_ref": [ "r2", "r11", "r20", "r114", "r428" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).", "label": "Due From Related Parties Current", "terseLabel": "Related party receivables" } } }, "localname": "DueFromRelatedPartiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_EarningsPerShareAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Earnings Per Share [Abstract]", "terseLabel": "Per share data:" } } }, "localname": "EarningsPerShareAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "stringItemType" }, "us-gaap_EarningsPerShareBasic": { "auth_ref": [ "r71", "r124", "r128", "r132", "r133", "r134", "r137", "r488", "r513" ], "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 earnings per share" } } }, "localname": "EarningsPerShareBasic", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfBasicEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "perShareItemType" }, "us-gaap_EarningsPerShareBasicAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Earnings Per Share Basic [Abstract]", "terseLabel": "Basic earnings per share", "verboseLabel": "Basic earnings per share:" } } }, "localname": "EarningsPerShareBasicAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfBasicEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "stringItemType" }, "us-gaap_EarningsPerShareDiluted": { "auth_ref": [ "r71", "r124", "r128", "r132", "r133", "r134", "r137", "r488", "r513" ], "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", "positiveTerseLabel": "Fully diluted earnings per share", "terseLabel": "Fully diluted earnings per share" } } }, "localname": "EarningsPerShareDiluted", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "perShareItemType" }, "us-gaap_EarningsPerShareDilutedAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Earnings Per Share Diluted [Abstract]", "terseLabel": "Fully diluted earnings per share", "verboseLabel": "Fully diluted earnings per share:" } } }, "localname": "EarningsPerShareDilutedAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "stringItemType" }, "us-gaap_EarningsPerShareTextBlock": { "auth_ref": [ "r138" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for earnings per share.", "label": "Earnings Per Share [Text Block]", "terseLabel": "Earnings Per Share and Weighted-Average Shares Outstanding" } } }, "localname": "EarningsPerShareTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstanding" ], "xbrltype": "textBlockItemType" }, "us-gaap_EmployeeRelatedLiabilitiesCurrent": { "auth_ref": [ "r37" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10170.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).", "label": "Employee Related Liabilities Current", "terseLabel": "Accrued compensation" } } }, "localname": "EmployeeRelatedLiabilitiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions": { "auth_ref": [ "r298" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.", "label": "Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Share Based Awards Other Than Options", "terseLabel": "Unrecognized compensation expense related to unvested RSUs" } } }, "localname": "EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_EquityAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Equity [Abstract]" } } }, "localname": "EquityAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_EquityComponentDomain": { "auth_ref": [ "r243" ], "lang": { "en-US": { "role": { "documentation": "Components of equity are the parts of the total Equity balance including that which is allocated to common, preferred, treasury stock, retained earnings, etc.", "label": "Equity Component [Domain]", "terseLabel": "Equity Component" } } }, "localname": "EquityComponentDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "domainItemType" }, "us-gaap_EquityMethodInvestmentDividendsOrDistributions": { "auth_ref": [ "r69", "r96", "r104", "r511" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.", "label": "Equity Method Investment Dividends Or Distributions", "terseLabel": "Distributions received" } } }, "localname": "EquityMethodInvestmentDividendsOrDistributions", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_EquityMethodInvestmentOwnershipPercentage": { "auth_ref": [ "r170" ], "lang": { "en-US": { "role": { "documentation": "The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.", "label": "Equity Method Investment Ownership Percentage", "terseLabel": "Equity method investment ownership percentage" } } }, "localname": "EquityMethodInvestmentOwnershipPercentage", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "us-gaap_EquityMethodInvestments": { "auth_ref": [ "r28", "r152", "r169" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail": { "order": 10030.0, "parentTag": "us-gaap_OtherAssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.", "label": "Equity Method Investments", "terseLabel": "Equity method investments" } } }, "localname": "EquityMethodInvestments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_EquityMethodInvestmentsAndJointVenturesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Equity Method Investments And Joint Ventures [Abstract]" } } }, "localname": "EquityMethodInvestmentsAndJointVenturesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_EquityMethodInvestmentsDisclosureTextBlock": { "auth_ref": [ "r172", "r351" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for equity method investments and joint ventures. Equity method investments are investments that give the investor the ability to exercise significant influence over the operating and financial policies of an investee. Joint ventures are entities owned and operated by a small group of businesses as a separate and specific business or project for the mutual benefit of the members of the group.", "label": "Equity Method Investments Disclosure [Text Block]", "terseLabel": "Investments" } } }, "localname": "EquityMethodInvestmentsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestments" ], "xbrltype": "textBlockItemType" }, "us-gaap_EscrowDeposit": { "auth_ref": [ "r482" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.", "label": "Escrow Deposit", "terseLabel": "Escrow funds amount" } } }, "localname": "EscrowDeposit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEscrowAndCustodialFundsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_EstimateOfFairValueFairValueDisclosureMember": { "auth_ref": [ "r388" ], "lang": { "en-US": { "role": { "documentation": "Measured as an estimate of fair value.", "label": "Estimate Of Fair Value Fair Value Disclosure [Member]", "terseLabel": "Fair Value [Member]" } } }, "localname": "EstimateOfFairValueFairValueDisclosureMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail" ], "xbrltype": "domainItemType" }, "us-gaap_ExcessCapital": { "auth_ref": [ "r497" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The amount by which the company's Total Capital exceeds the minimum required for capital adequacy purposes.", "label": "Excess Capital", "terseLabel": "Amount of capital in excess of aggregate regulatory requirements" } } }, "localname": "ExcessCapital", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "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 Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]" } } }, "localname": "FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable": { "auth_ref": [ "r371", "r372", "r373", "r384" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about asset and liability measured at fair value on recurring and nonrecurring basis.", "label": "Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table]", "terseLabel": "Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table]" } } }, "localname": "FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount": { "auth_ref": [ "r373" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.", "label": "Fair Value Assets Level1 To Level2 Transfers Amount", "terseLabel": "Fair value assets transfers from level 1 to level 2" } } }, "localname": "FairValueAssetsLevel1ToLevel2TransfersAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount": { "auth_ref": [ "r373" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.", "label": "Fair Value Assets Level2 To Level1 Transfers Amount", "terseLabel": "Fair value assets transfers from level 2 to level 1" } } }, "localname": "FairValueAssetsLevel2ToLevel1TransfersAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss": { "auth_ref": [ "r381" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.", "label": "Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss", "terseLabel": "Assets, Unrealized gains (losses) outstanding" } } }, "localname": "FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain": { "auth_ref": [ "r377" ], "lang": { "en-US": { "role": { "documentation": "Class of asset.", "label": "Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation By Asset Class [Domain]", "terseLabel": "Asset Class" } } }, "localname": "FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]", "terseLabel": "Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]" } } }, "localname": "FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueByAssetClassAxis": { "auth_ref": [ "r371", "r384" ], "lang": { "en-US": { "role": { "documentation": "Information by class of asset.", "label": "Fair Value By Asset Class [Axis]", "terseLabel": "Asset Class" } } }, "localname": "FairValueByAssetClassAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueByBalanceSheetGroupingTable": { "auth_ref": [ "r371", "r389", "r390" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.", "label": "Fair Value By Balance Sheet Grouping [Table]", "terseLabel": "Fair Value By Balance Sheet Grouping [Table]" } } }, "localname": "FairValueByBalanceSheetGroupingTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueByFairValueHierarchyLevelAxis": { "auth_ref": [ "r272", "r273", "r275", "r372", "r439" ], "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 By Fair Value Hierarchy Level [Axis]", "terseLabel": "Fair Value Hierarchy and NAV" } } }, "localname": "FairValueByFairValueHierarchyLevelAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueByMeasurementBasisAxis": { "auth_ref": [ "r371", "r385" ], "lang": { "en-US": { "role": { "documentation": "Information by measurement basis.", "label": "Fair Value By Measurement Basis [Axis]", "terseLabel": "Measurement Basis" } } }, "localname": "FairValueByMeasurementBasisAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueByMeasurementFrequencyAxis": { "auth_ref": [ "r371", "r372", "r375", "r376", "r386" ], "lang": { "en-US": { "role": { "documentation": "Information by measurement frequency.", "label": "Fair Value By Measurement Frequency [Axis]", "terseLabel": "Measurement Frequency" } } }, "localname": "FairValueByMeasurementFrequencyAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueConcentrationOfRiskLoansReceivable": { "auth_ref": [ "r165" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.", "label": "Fair Value Concentration Of Risk Loans Receivable", "terseLabel": "Credit risk loans" } } }, "localname": "FairValueConcentrationOfRiskLoansReceivable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueDisclosureItemAmountsDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Measurement basis, for example, but not limited to, reported value, fair value, portion at fair value, portion at other than fair value.", "label": "Fair Value Disclosure Item Amounts [Domain]", "terseLabel": "Fair Value Measurement" } } }, "localname": "FairValueDisclosureItemAmountsDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueDisclosuresAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Fair Value Disclosures [Abstract]" } } }, "localname": "FairValueDisclosuresAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_FairValueDisclosuresTextBlock": { "auth_ref": [ "r383" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.", "label": "Fair Value Disclosures [Text Block]", "terseLabel": "Fair Value of Financial Assets and Liabilities" } } }, "localname": "FairValueDisclosuresTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilities" ], "xbrltype": "textBlockItemType" }, "us-gaap_FairValueInputsLevel1Member": { "auth_ref": [ "r272", "r273", "r275", "r372", "r440" ], "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 Level1 [Member]", "terseLabel": "Level 1 [Member]" } } }, "localname": "FairValueInputsLevel1Member", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueInputsLevel2Member": { "auth_ref": [ "r272", "r273", "r275", "r372", "r441" ], "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 Level2 [Member]", "terseLabel": "Level 2 [Member]" } } }, "localname": "FairValueInputsLevel2Member", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueInputsLevel3Member": { "auth_ref": [ "r272", "r273", "r275", "r372", "r442" ], "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 Level3 [Member]", "terseLabel": "Level 3 [Member]" } } }, "localname": "FairValueInputsLevel3Member", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueLiabilitiesLevel1ToLevel2TransfersAmount": { "auth_ref": [ "r373" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.", "label": "Fair Value Liabilities Level1 To Level2 Transfers Amount", "terseLabel": "Fair value liabilities transfers from level 1 to level 2" } } }, "localname": "FairValueLiabilitiesLevel1ToLevel2TransfersAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueLiabilitiesLevel2ToLevel1TransfersAmount": { "auth_ref": [ "r373" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.", "label": "Fair Value Liabilities Level2 To Level1 Transfers Amount", "terseLabel": "Fair value liabilities transfers from level 2 to level 1" } } }, "localname": "FairValueLiabilitiesLevel2ToLevel1TransfersAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss": { "auth_ref": [ "r381" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held.", "label": "Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss", "terseLabel": "Liabilities, Unrealized gains (losses) outstanding" } } }, "localname": "FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems": { "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 Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]", "terseLabel": "Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]" } } }, "localname": "FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable": { "auth_ref": [ "r377", "r384" ], "lang": { "en-US": { "role": { "documentation": "Schedule of information required and determined to be provided for purposes of reconciling beginning and ending balances of fair value measurements of liabilities using significant unobservable inputs (level 3). Separately presenting changes during the period, attributable to: (1) total gains or losses for the period (realized and unrealized) and location reported in the statement of income (or activities); (2) purchases, sales, issuances, and settlements (net); (3) transfers in and/or out of Level 3.", "label": "Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Table]", "terseLabel": "Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Table]" } } }, "localname": "FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FairValueMeasurementFrequencyDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Measurement frequency.", "label": "Fair Value Measurement Frequency [Domain]", "terseLabel": "Measurement Frequency" } } }, "localname": "FairValueMeasurementFrequencyDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3": { "auth_ref": [ "r380" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Liability Transfers Into Level3", "terseLabel": "Fair value liabilities transfers Into level 3" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3": { "auth_ref": [ "r380" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Liability Transfers Out Of Level3", "terseLabel": "Fair value liabilities transfers out of level 3" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1": { "auth_ref": [ "r378" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1", "terseLabel": "Assets, Total realized and unrealized gains (losses) included in Net income" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues": { "auth_ref": [ "r379" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Issues", "terseLabel": "Assets, Issuances" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements": { "auth_ref": [ "r379" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements", "negatedLabel": "Assets, Settlements" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3": { "auth_ref": [ "r380" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3", "terseLabel": "Fair value assets transfers Into level 3" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3": { "auth_ref": [ "r380" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3", "terseLabel": "Fair value assets transfers out of level 3" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue": { "auth_ref": [ "r377" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value", "periodEndLabel": "Assets, Closing Balance", "periodStartLabel": "Assets, Opening Balance", "verboseLabel": "Assets" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings": { "auth_ref": [ "r378" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings", "terseLabel": "Liabilities, Total realized and unrealized gains (losses) included in Net income" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues": { "auth_ref": [ "r379" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Issues", "terseLabel": "Liabilities, Issuances" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements": { "auth_ref": [ "r379" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements", "negatedLabel": "Liabilities, Settlements" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue": { "auth_ref": [ "r377" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.", "label": "Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value", "periodEndLabel": "Liabilities, Closing Balance", "periodStartLabel": "Liabilities, Opening Balance", "positiveLabel": "Present value of expected payments related to contingent consideration", "verboseLabel": "Liabilities" } } }, "localname": "FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "monetaryItemType" }, "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 Measurements Fair Value Hierarchy [Domain]", "terseLabel": "Fair Value Hierarchy and NAV" } } }, "localname": "FairValueMeasurementsFairValueHierarchyDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueMeasurementsNonrecurringMember": { "auth_ref": [ "r371", "r372", "r375", "r376", "r382", "r386" ], "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 Measurements Nonrecurring [Member]", "terseLabel": "Fair Value, Measurements, Nonrecurring [Member]" } } }, "localname": "FairValueMeasurementsNonrecurringMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FairValueOptionQuantitativeDisclosuresTextBlock": { "auth_ref": [ "r395", "r396", "r397", "r398" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of information about asset and liability measured at fair value under fair value option.", "label": "Fair Value Option Quantitative Disclosures [Text Block]", "terseLabel": "Quantitative Information about Level 3 Fair Value Measurements" } } }, "localname": "FairValueOptionQuantitativeDisclosuresTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_FeesAndCommissionsMortgageBankingAndServicing": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetSummaryOfGainsFromMortgageBankingActivitiesOriginationsNetDetail": { "order": 10010.0, "parentTag": "us-gaap_GainLossOnSaleOfMortgageLoans", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.", "label": "Fees And Commissions Mortgage Banking And Servicing", "terseLabel": "Loan originations related fees and sales premiums, net", "verboseLabel": "Mortgage servicing right recognized" } } }, "localname": "FeesAndCommissionsMortgageBankingAndServicing", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetSummaryOfGainsFromMortgageBankingActivitiesOriginationsNetDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FinancialInstrumentAxis": { "auth_ref": [ "r173", "r175", "r176", "r178", "r180", "r185", "r186", "r187", "r188" ], "lang": { "en-US": { "role": { "documentation": "Information by type of financial instrument.", "label": "Financial Instrument [Axis]", "terseLabel": "Financial Instrument" } } }, "localname": "FinancialInstrumentAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Financial Instruments Financial Assets Balance Sheet Groupings [Abstract]", "terseLabel": "Assets:" } } }, "localname": "FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Financial Instruments Financial Liabilities Balance Sheet Groupings [Abstract]", "terseLabel": "Liabilities:" } } }, "localname": "FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FinancialServicesLiabilities": { "auth_ref": [ "r483", "r510" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "For entities that provide full or partial financing and servicing for customers supplementary to its major operations (such as a manufacturer or a homebuilder providing and servicing loans to buyers), represents the liabilities associated with such activities, including accounts payable and accrued liabilities.", "label": "Financial Services Liabilities", "terseLabel": "Outstanding principal balances of credit risk loans being serviced" } } }, "localname": "FinancialServicesLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis": { "auth_ref": [ "r160", "r162", "r163", "r176", "r178", "r180", "r181", "r182", "r183", "r184" ], "lang": { "en-US": { "role": { "documentation": "Information by class of financing receivable determined on the basis of initial measurement attribute, risk characteristics and method of monitoring and assessing credit risk.", "label": "Financing Receivable Recorded Investment By Class Of Financing Receivable [Axis]", "terseLabel": "Class of Financing Receivable" } } }, "localname": "FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Financing receivables determined on the basis of initial measurement attribute, risk characteristics and method of monitoring and assessing credit risk.", "label": "Financing Receivable Recorded Investment Class Of Financing Receivable [Domain]", "terseLabel": "Class of Financing Receivable" } } }, "localname": "FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus": { "auth_ref": [ "r161", "r177" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of financing receivable on nonaccrual status.", "label": "Financing Receivable Recorded Investment Nonaccrual Status", "terseLabel": "Loans held for sale in nonaccrual status" } } }, "localname": "FinancingReceivableRecordedInvestmentNonaccrualStatus", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FinancingReceivableRecordedInvestmentPastDue": { "auth_ref": [ "r163", "r176", "r184" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of financing receivable past due.", "label": "Financing Receivable Recorded Investment Past Due", "terseLabel": "Loans held for sale past due" } } }, "localname": "FinancingReceivableRecordedInvestmentPastDue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember": { "auth_ref": [ "r184" ], "lang": { "en-US": { "role": { "documentation": "Financial asset equal to or greater than 90 days past due.", "label": "Financing Receivables Equal To Greater Than90 Days Past Due [Member]", "terseLabel": "Greater Than 90 Days Past Due [Member]" } } }, "localname": "FinancingReceivablesEqualToGreaterThan90DaysPastDueMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FinancingReceivablesPeriodPastDueAxis": { "auth_ref": [ "r176", "r184" ], "lang": { "en-US": { "role": { "documentation": "Information by time period financial asset is past due.", "label": "Financing Receivables Period Past Due [Axis]", "terseLabel": "Financial Asset, Period Past Due" } } }, "localname": "FinancingReceivablesPeriodPastDueAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FinancingReceivablesPeriodPastDueDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Period in which financial asset is past due. Element name and standard label in Financial Asset, [numeric lower end] to [numeric higher end] [date measure] Past Due [Member] or Financial Asset, Greater Than [low end numeric value] [date measure] Past Due [Member] or Financial Asset, Less Than [high end numeric value] [date measure] Past Due [Member] formats.", "label": "Financing Receivables Period Past Due [Domain]", "terseLabel": "Financial Asset, Period Past Due" } } }, "localname": "FinancingReceivablesPeriodPastDueDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FinancingReceivablesTextBlock": { "auth_ref": [ "r165", "r166" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for financing receivable.", "label": "Financing Receivables [Text Block]", "terseLabel": "Loans Held for Sale, at Fair Value" } } }, "localname": "FinancingReceivablesTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValue" ], "xbrltype": "textBlockItemType" }, "us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization": { "auth_ref": [ "r208" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail": { "order": 11100.0, "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", "negatedLabel": "Definite life, Accumulated Amortization" } } }, "localname": "FiniteLivedIntangibleAssetsAccumulatedAmortization", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail": { "order": 10060.0, "parentTag": "nmrk_FiniteLivedIntangibleAssetsExpectedAmortizationExpense", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth 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 After Year Five", "terseLabel": "Thereafter" } } }, "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail": { "order": 10010.0, "parentTag": "nmrk_FiniteLivedIntangibleAssetsExpectedAmortizationExpense", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the 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 Remainder Of Fiscal Year", "terseLabel": "2019" } } }, "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive": { "auth_ref": [ "r210" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail": { "order": 10050.0, "parentTag": "nmrk_FiniteLivedIntangibleAssetsExpectedAmortizationExpense", "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 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": "Finite Lived Intangible Assets Amortization Expense Year Five", "terseLabel": "2023" } } }, "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseYearFive", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour": { "auth_ref": [ "r210" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail": { "order": 10040.0, "parentTag": "nmrk_FiniteLivedIntangibleAssetsExpectedAmortizationExpense", "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": "2022" } } }, "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseYearFour", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree": { "auth_ref": [ "r210" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail": { "order": 10030.0, "parentTag": "nmrk_FiniteLivedIntangibleAssetsExpectedAmortizationExpense", "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": "2021" } } }, "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseYearThree", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo": { "auth_ref": [ "r210" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail": { "order": 10020.0, "parentTag": "nmrk_FiniteLivedIntangibleAssetsExpectedAmortizationExpense", "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": "2020" } } }, "localname": "FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetScheduleOfEstimatedFutureAmortizationOfDefiniteLifeIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis": { "auth_ref": [ "r202", "r205", "r208", "r212", "r461" ], "lang": { "en-US": { "role": { "documentation": "Information by major type or class of finite-lived intangible assets.", "label": "Finite Lived Intangible Assets By Major Class [Axis]", "terseLabel": "Finite-Lived Intangible Assets by Major Class" } } }, "localname": "FiniteLivedIntangibleAssetsByMajorClassAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_FiniteLivedIntangibleAssetsGross": { "auth_ref": [ "r208", "r461" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail": { "order": 11090.0, "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": "Definite life, Gross Amount" } } }, "localname": "FiniteLivedIntangibleAssetsGross", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain": { "auth_ref": [ "r202", "r207" ], "lang": { "en-US": { "role": { "documentation": "The major class of finite-lived intangible asset (for example, patents, trademarks, copyrights, etc.) A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.", "label": "Finite Lived Intangible Assets Major Class Name [Domain]", "terseLabel": "Finite-Lived Intangible Assets, Major Class Name" } } }, "localname": "FiniteLivedIntangibleAssetsMajorClassNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_FiniteLivedIntangibleAssetsNet": { "auth_ref": [ "r208" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail": { "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": "Definite life, Net Carrying Amount" } } }, "localname": "FiniteLivedIntangibleAssetsNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ForwardContractsMember": { "auth_ref": [ "r364" ], "lang": { "en-US": { "role": { "documentation": "Contracts negotiated between two parties to purchase and sell a specific quantity of a financial instrument, foreign currency, or commodity at a price specified at origination of the contract, with delivery and settlement at a specified future date.", "label": "Forward Contracts [Member]", "terseLabel": "Forward Contracts [Member]", "verboseLabel": "Forward Sale Contracts [Member]" } } }, "localname": "ForwardContractsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_GainLossOnInvestments": { "auth_ref": [ "r81", "r104", "r167" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of realized and unrealized gain (loss) on investment.", "label": "Gain Loss On Investments", "terseLabel": "Realized and unrealized gains, net" } } }, "localname": "GainLossOnInvestments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_GainLossOnSaleOfMortgageLoans": { "auth_ref": [ "r104", "r515", "r516", "r517" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetSummaryOfGainsFromMortgageBankingActivitiesOriginationsNetDetail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail": { "order": 10020.0, "parentTag": "us-gaap_Revenues", "weight": 1.0 }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10170.0, "parentTag": "us-gaap_Revenues", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.", "label": "Gain Loss On Sale Of Mortgage Loans", "terseLabel": "Gains from mortgage banking activities/originations, net", "totalLabel": "Total" } } }, "localname": "GainLossOnSaleOfMortgageLoans", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGainsFromMortgageBankingActivitiesOriginationsNetSummaryOfGainsFromMortgageBankingActivitiesOriginationsNetDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_GeneralAndAdministrativeExpense": { "auth_ref": [ "r80" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10110.0, "parentTag": "us-gaap_CostsAndExpenses", "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": "Operating, administrative and other" } } }, "localname": "GeneralAndAdministrativeExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_Goodwill": { "auth_ref": [ "r191", "r193" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail": { "order": 10070.0, "parentTag": "us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets", "weight": 1.0 }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10220.0, "parentTag": "us-gaap_Assets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.", "label": "Goodwill", "periodEndLabel": "Ending Balance", "periodStartLabel": "Beginning Balance", "terseLabel": "Goodwill", "verboseLabel": "Additional goodwill recognized" } } }, "localname": "Goodwill", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetSummaryOfChangesInCarryingAmountOfGoodwillDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_GoodwillAcquiredDuringPeriod": { "auth_ref": [ "r194" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.", "label": "Goodwill Acquired During Period", "terseLabel": "Acquisitions" } } }, "localname": "GoodwillAcquiredDuringPeriod", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetSummaryOfChangesInCarryingAmountOfGoodwillDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Goodwill And Intangible Assets Disclosure [Abstract]" } } }, "localname": "GoodwillAndIntangibleAssetsDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock": { "auth_ref": [ "r213" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for goodwill and intangible assets.", "label": "Goodwill And Intangible Assets Disclosure [Text Block]", "terseLabel": "Goodwill and Other Intangible Assets, Net" } } }, "localname": "GoodwillAndIntangibleAssetsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNet" ], "xbrltype": "textBlockItemType" }, "us-gaap_GoodwillImpairmentLoss": { "auth_ref": [ "r104", "r192", "r195", "r198" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.", "label": "Goodwill Impairment Loss", "terseLabel": "Impairment of goodwill" } } }, "localname": "GoodwillImpairmentLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_GoodwillPurchaseAccountingAdjustments": { "auth_ref": [ "r196", "r310" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.", "label": "Goodwill Purchase Accounting Adjustments", "terseLabel": "Measurement period adjustments" } } }, "localname": "GoodwillPurchaseAccountingAdjustments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetSummaryOfChangesInCarryingAmountOfGoodwillDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_GuaranteeObligationsByNatureAxis": { "auth_ref": [ "r235" ], "lang": { "en-US": { "role": { "documentation": "Information by nature of guarantee.", "label": "Guarantee Obligations By Nature [Axis]", "terseLabel": "Guarantor Obligations, Nature" } } }, "localname": "GuaranteeObligationsByNatureAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_GuaranteeObligationsLineItems": { "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": "Guarantee Obligations [Line Items]", "terseLabel": "Guarantee Obligations [Line Items]" } } }, "localname": "GuaranteeObligationsLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_GuaranteeObligationsMaximumExposure": { "auth_ref": [ "r234" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.", "label": "Guarantee Obligations Maximum Exposure", "terseLabel": "Maximum pre-credit enhancement loss exposure" } } }, "localname": "GuaranteeObligationsMaximumExposure", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_GuaranteeObligationsNatureDomain": { "auth_ref": [ "r233" ], "lang": { "en-US": { "role": { "documentation": "Represents a description of the nature of the guarantee or each group of similar guarantees.", "label": "Guarantee Obligations Nature [Domain]", "terseLabel": "Guarantor Obligations, Nature" } } }, "localname": "GuaranteeObligationsNatureDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_GuaranteesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Guarantees [Abstract]" } } }, "localname": "GuaranteesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_GuaranteesTextBlock": { "auth_ref": [ "r237" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for each guarantee obligation, or each group of similar guarantee obligations, including (a) the nature of the guarantee, including its term, how it arose, and the events or circumstances that would require the guarantor to perform under the guarantee; (b) the maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee; (c) the current carrying amount of the liability, if any, for the guarantor's obligations under the guarantee; and (d) the nature of any recourse provisions under the guarantee, and any assets held either as collateral or by third parties, and any relevant related party disclosure. Excludes disclosures about product warranties.", "label": "Guarantees [Text Block]", "terseLabel": "Financial Guarantee Liability" } } }, "localname": "GuaranteesTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiability" ], "xbrltype": "textBlockItemType" }, "us-gaap_GuarantyLiabilities": { "auth_ref": [ "r229", "r230", "r483", "r510" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail": { "order": 10060.0, "parentTag": "us-gaap_OtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "This item represents a non-contingent liability for the fair value of an obligation to stand ready to perform over the term of a guaranty issued in the event that specified triggering events or conditions occur.", "label": "Guaranty Liabilities", "negatedPeriodEndLabel": "Ending Balance", "negatedPeriodStartLabel": "Beginning Balance", "terseLabel": "Financial guarantee liability" } } }, "localname": "GuarantyLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilitySummaryOfChangesInEstimatedLiabilityUnderGuaranteeLiabilityDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_HedgingDesignationAxis": { "auth_ref": [ "r355", "r366" ], "lang": { "en-US": { "role": { "documentation": "Information by designation of purpose of derivative instrument.", "label": "Hedging Designation [Axis]", "terseLabel": "Hedging Designation" } } }, "localname": "HedgingDesignationAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_HedgingDesignationDomain": { "auth_ref": [ "r355" ], "lang": { "en-US": { "role": { "documentation": "Designation of purpose of derivative instrument.", "label": "Hedging Designation [Domain]", "terseLabel": "Hedging Designation" } } }, "localname": "HedgingDesignationDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_IPOMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "First sale of stock by a private company to the public.", "label": "I P O [Member]", "terseLabel": "IPO [Member]" } } }, "localname": "IPOMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest": { "auth_ref": [ "r68", "r124", "r474", "r486", "r514" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10030.0, "parentTag": "us-gaap_ProfitLoss", "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 Extraordinary Items Noncontrolling Interest", "totalLabel": "Income before income taxes and noncontrolling interests" } } }, "localname": "IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeLossFromEquityMethodInvestments": { "auth_ref": [ "r69", "r104", "r149", "r169", "r485", "r511" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10430.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of income (loss) for proportionate share of equity method investee's income (loss).", "label": "Income Loss From Equity Method Investments", "negatedLabel": "Income from an equity method investment", "verboseLabel": "Equity Income" } } }, "localname": "IncomeLossFromEquityMethodInvestments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeStatementAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Income Statement [Abstract]" } } }, "localname": "IncomeStatementAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by name of disposal group.", "label": "Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Axis]", "terseLabel": "Disposal Group Name" } } }, "localname": "IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_IncomeStatementLocationAxis": { "auth_ref": [ "r218" ], "lang": { "en-US": { "role": { "documentation": "Information by location in the income statement.", "label": "Income Statement Location [Axis]", "terseLabel": "Income Statement Location" } } }, "localname": "IncomeStatementLocationAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "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" } } }, "localname": "IncomeStatementLocationDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_IncomeTaxDisclosureAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Income Tax Disclosure [Abstract]" } } }, "localname": "IncomeTaxDisclosureAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_IncomeTaxDisclosureTextBlock": { "auth_ref": [ "r309" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureIncomeTaxes" ], "xbrltype": "textBlockItemType" }, "us-gaap_IncomeTaxExpenseBenefit": { "auth_ref": [ "r113", "r150", "r308" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10040.0, "parentTag": "us-gaap_ProfitLoss", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.", "label": "Income Tax Expense Benefit", "terseLabel": "Provision for income taxes" } } }, "localname": "IncomeTaxExpenseBenefit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncomeTaxesPaid": { "auth_ref": [ "r100", "r107" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.", "label": "Income Taxes Paid", "terseLabel": "Taxes" } } }, "localname": "IncomeTaxesPaid", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInAccountsReceivable": { "auth_ref": [ "r103" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10270.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.", "label": "Increase Decrease In Accounts Receivable", "negatedLabel": "Receivables, net" } } }, "localname": "IncreaseDecreaseInAccountsReceivable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInAccruedSalaries": { "auth_ref": [ "r103" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10300.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the period in accrued salaries.", "label": "Increase Decrease In Accrued Salaries", "terseLabel": "Accrued compensation" } } }, "localname": "IncreaseDecreaseInAccruedSalaries", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInDueFromEmployeeCurrent": { "auth_ref": [ "r103" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10280.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in the amount due within one year (or one business cycle) from employees for floats, allowances and loans (generally evidenced by promissory notes).", "label": "Increase Decrease In Due From Employee Current", "negatedLabel": "Loans, forgivable loans and other receivables from employees and partners" } } }, "localname": "IncreaseDecreaseInDueFromEmployeeCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInDueToRelatedParties": { "auth_ref": [ "r103" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10320.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in the aggregate amount of obligations to be paid to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entities' management; an entity and its principal owners, management, or member of their immediate families; affiliates; or other parties with the ability to exert significant influence.", "label": "Increase Decrease In Due To Related Parties", "terseLabel": "Payables to related parties" } } }, "localname": "IncreaseDecreaseInDueToRelatedParties", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "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.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities": { "auth_ref": [ "r103" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10310.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in other obligations or expenses incurred but not yet paid.", "label": "Increase Decrease In Other Accounts Payable And Accrued Liabilities", "terseLabel": "Accounts payable, accrued expenses and other liabilities" } } }, "localname": "IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInOtherOperatingAssets": { "auth_ref": [ "r103" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10290.0, "parentTag": "us-gaap_NetCashProvidedByUsedInOperatingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) in operating assets classified as other.", "label": "Increase Decrease In Other Operating Assets", "negatedLabel": "Other assets" } } }, "localname": "IncreaseDecreaseInOtherOperatingAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncreaseDecreaseInSecuritiesLoanedTransactions": { "auth_ref": [ "r103" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10140.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The increase (decrease) during the reporting period in the liability arising from securities loaned transactions.", "label": "Increase Decrease In Securities Loaned Transactions", "terseLabel": "Securities loaned" } } }, "localname": "IncreaseDecreaseInSecuritiesLoanedTransactions", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements": { "auth_ref": [ "r129", "r136" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail": { "order": 10030.0, "parentTag": "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding", "weight": 1.0 } }, "lang": { "en-US": { "role": { "documentation": "Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.", "label": "Incremental Common Shares Attributable To Share Based Payment Arrangements", "terseLabel": "RSUs" } } }, "localname": "IncrementalCommonSharesAttributableToShareBasedPaymentArrangements", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis": { "auth_ref": [ "r204", "r211" ], "lang": { "en-US": { "role": { "documentation": "Information by type or class of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.", "label": "Indefinite Lived Intangible Assets By Major Class [Axis]", "terseLabel": "Indefinite-lived Intangible Assets" } } }, "localname": "IndefiniteLivedIntangibleAssetsByMajorClassAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill": { "auth_ref": [ "r211" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.", "label": "Indefinite Lived Intangible Assets Excluding Goodwill", "terseLabel": "Indefinite life, intangible assets" } } }, "localname": "IndefiniteLivedIntangibleAssetsExcludingGoodwill", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain": { "auth_ref": [ "r204", "r211" ], "lang": { "en-US": { "role": { "documentation": "The major class of indefinite-lived intangible asset (for example, trade names, etc. but not all-inclusive), excluding goodwill. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of the company.", "label": "Indefinite Lived Intangible Assets Major Class Name [Domain]", "terseLabel": "Indefinite-lived Intangible Assets, Major Class Name" } } }, "localname": "IndefiniteLivedIntangibleAssetsMajorClassNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis": { "auth_ref": [ "r268" ], "lang": { "en-US": { "role": { "documentation": "Information about effect of transition method for cumulative effect in initial period of application.", "label": "Initial Application Period Cumulative Effect Transition [Axis]", "terseLabel": "Initial Application Period Cumulative Effect Transition" } } }, "localname": "InitialApplicationPeriodCumulativeEffectTransitionAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Effect of transition method for cumulative effect in initial period of application.", "label": "Initial Application Period Cumulative Effect Transition [Domain]", "terseLabel": "Initial Application Period Cumulative Effect Transition" } } }, "localname": "InitialApplicationPeriodCumulativeEffectTransitionDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_IntangibleAssetsGrossExcludingGoodwill": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail": { "order": 11050.0, "parentTag": "us-gaap_IntangibleAssetsNetExcludingGoodwill", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount before accumulated amortization of intangible assets, excluding goodwill.", "label": "Intangible Assets Gross Excluding Goodwill", "terseLabel": "Gross Amount" } } }, "localname": "IntangibleAssetsGrossExcludingGoodwill", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_IntangibleAssetsNetExcludingGoodwill": { "auth_ref": [ "r200", "r206" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10260.0, "parentTag": "us-gaap_Assets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.", "label": "Intangible Assets Net Excluding Goodwill", "terseLabel": "Other intangible assets, net", "totalLabel": "Net Carrying Amount" } } }, "localname": "IntangibleAssetsNetExcludingGoodwill", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_InterestAndFeeIncomeLoansHeldForSaleMortgages": { "auth_ref": [ "r489" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Interest and fee income from mortgage loans considered to be held-for-sale.", "label": "Interest And Fee Income Loans Held For Sale Mortgages", "terseLabel": "Interest income on Loans held for sale" } } }, "localname": "InterestAndFeeIncomeLoansHeldForSaleMortgages", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_InterestExpenseLongTermDebt": { "auth_ref": [ "r491" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Aggregate amount of interest paid or due on all long-term debt.", "label": "Interest Expense Long Term Debt", "verboseLabel": "Interest expense" } } }, "localname": "InterestExpenseLongTermDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_InterestExpenseRelatedParty": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of interest expense incurred on a debt or other obligation to related party.", "label": "Interest Expense Related Party", "terseLabel": "Interest expense" } } }, "localname": "InterestExpenseRelatedParty", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_InterestIncomeExpenseNet": { "auth_ref": [ "r490" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10060.0, "parentTag": "us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The net amount of operating interest income (expense).", "label": "Interest Income Expense Net", "terseLabel": "Interest expense, net" } } }, "localname": "InterestIncomeExpenseNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_InterestPaidNet": { "auth_ref": [ "r93", "r99", "r107" ], "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 Net", "terseLabel": "Interest" } } }, "localname": "InterestPaidNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_InterestRateLockCommitmentsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Commitments to extend credit where the interest rate is locked in advance of funds being disbursed for a specified period of time.", "label": "Interest Rate Lock Commitments [Member]", "terseLabel": "Rate Lock Commitments [Member]" } } }, "localname": "InterestRateLockCommitmentsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_InvestmentTypeAxis": { "auth_ref": [ "r527", "r528", "r529", "r530" ], "lang": { "en-US": { "role": { "documentation": "Information by type of investments.", "label": "Investment Type [Axis]", "terseLabel": "Investment Type" } } }, "localname": "InvestmentTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_InvestmentTypeCategorizationMember": { "auth_ref": [ "r527", "r528", "r529", "r530" ], "lang": { "en-US": { "role": { "documentation": "Asset obtained to generate income or appreciate in value.", "label": "Investment Type Categorization [Member]", "terseLabel": "Investments" } } }, "localname": "InvestmentTypeCategorizationMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_InvestmentsAllOtherInvestmentsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Investments All Other Investments [Abstract]" } } }, "localname": "InvestmentsAllOtherInvestmentsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Investments Debt And Equity Securities [Abstract]" } } }, "localname": "InvestmentsDebtAndEquitySecuritiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock": { "auth_ref": [ "r168", "r475", "r492", "r532" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for investments in certain debt and equity securities.", "label": "Investments In Debt And Marketable Equity Securities And Certain Trading Assets Disclosure [Text Block]", "terseLabel": "Marketable Securities" } } }, "localname": "InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecurities" ], "xbrltype": "textBlockItemType" }, "us-gaap_LeaseAndRentalExpense": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.", "label": "Lease And Rental Expense", "terseLabel": "Rent expense, including operating lease costs" } } }, "localname": "LeaseAndRentalExpense", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LeasesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Leases [Abstract]" } } }, "localname": "LeasesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "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.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_LesseeLeaseDescriptionTable": { "auth_ref": [ "r416" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_LesseeLeasesPolicyTextBlock": { "auth_ref": [ "r414" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of accounting policy for leasing arrangement entered into by lessee.", "label": "Lessee Leases Policy [Text Block]", "terseLabel": "Leases" } } }, "localname": "LesseeLeasesPolicyTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationPolicies" ], "xbrltype": "textBlockItemType" }, "us-gaap_LesseeOperatingLeaseExistenceOfOptionToExtend": { "auth_ref": [ "r415" ], "lang": { "en-US": { "role": { "documentation": "Indicates (true false) whether lessee has option to extend operating lease.", "label": "Lessee Operating Lease Existence Of Option To Extend", "terseLabel": "Operating lease, existence of option to extend" } } }, "localname": "LesseeOperatingLeaseExistenceOfOptionToExtend", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "booleanItemType" }, "us-gaap_LesseeOperatingLeaseExistenceOfOptionToTerminate": { "auth_ref": [ "r415" ], "lang": { "en-US": { "role": { "documentation": "Indicates (true false) whether lessee has option to terminate operating lease.", "label": "Lessee Operating Lease Existence Of Option To Terminate", "terseLabel": "Operating lease existence of option to terminate" } } }, "localname": "LesseeOperatingLeaseExistenceOfOptionToTerminate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "booleanItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock": { "auth_ref": [ "r423" ], "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 Future Minimum Rental Payments for Operating Leases under Topic 842" } } }, "localname": "LesseeOperatingLeaseLiabilityMaturityTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue": { "auth_ref": [ "r423" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail2": { "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.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive": { "auth_ref": [ "r423" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail": { "order": 10060.0, "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 after fifth fiscal year following latest fiscal year.", "label": "Lessee Operating Lease Liability Payments Due After Year Five", "terseLabel": "Thereafter" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive": { "auth_ref": [ "r423" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail": { "order": 10050.0, "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": "2023" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearFive", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour": { "auth_ref": [ "r423" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail": { "order": 10040.0, "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": "2022" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearFour", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree": { "auth_ref": [ "r423" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail": { "order": 10030.0, "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": "2021" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearThree", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo": { "auth_ref": [ "r423" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail": { "order": 10020.0, "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": "2020" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsDueYearTwo", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear": { "auth_ref": [ "r423" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail": { "order": 10010.0, "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": "2019" } } }, "localname": "LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount": { "auth_ref": [ "r423" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail2": { "order": 10010.0, "parentTag": "us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.", "label": "Lessee Operating Lease Liability Undiscounted Excess Amount", "terseLabel": "Less: Interest" } } }, "localname": "LesseeOperatingLeaseLiabilityUndiscountedExcessAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LesseeOperatingLeaseOptionToExtend": { "auth_ref": [ "r415" ], "lang": { "en-US": { "role": { "documentation": "Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.", "label": "Lessee Operating Lease Option To Extend", "terseLabel": "Operating lease option to extend description" } } }, "localname": "LesseeOperatingLeaseOptionToExtend", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_LesseeOperatingLeaseRenewalTerm": { "auth_ref": [ "r415" ], "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": "Options to extend the lease", "verboseLabel": "Operating lease option to extend" } } }, "localname": "LesseeOperatingLeaseRenewalTerm", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "us-gaap_LesseeOperatingLeaseTermOfContract": { "auth_ref": [ "r415" ], "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 remaining term" } } }, "localname": "LesseeOperatingLeaseTermOfContract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "us-gaap_LesseeOperatingLeasesTextBlock": { "auth_ref": [ "r425" ], "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": "Leases" } } }, "localname": "LesseeOperatingLeasesTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeases" ], "xbrltype": "textBlockItemType" }, "us-gaap_Liabilities": { "auth_ref": [ "r35" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10010.0, "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", "terseLabel": "Liabilities", "totalLabel": "Total liabilities" } } }, "localname": "Liabilities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LiabilitiesAndStockholdersEquity": { "auth_ref": [ "r26", "r481", "r505" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "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 Stockholders Equity", "totalLabel": "Total liabilities, redeemable partnership interests, and equity" } } }, "localname": "LiabilitiesAndStockholdersEquity", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LiabilitiesAndStockholdersEquityAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Liabilities And Stockholders Equity [Abstract]", "terseLabel": "Liabilities, Redeemable Partnership Interests, and Equity:" } } }, "localname": "LiabilitiesAndStockholdersEquityAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_LiabilitiesCurrent": { "auth_ref": [ "r38" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10130.0, "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.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "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.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_LiabilitiesFairValueDisclosure": { "auth_ref": [ "r371" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Fair value of financial and nonfinancial obligations.", "label": "Liabilities Fair Value Disclosure", "totalLabel": "Total" } } }, "localname": "LiabilitiesFairValueDisclosure", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LiabilitiesTotalMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Carrying amount as of the balance sheet date of total liabilities, when it serves as a benchmark in a concentration of risk calculation. Sum of all reported liabilities as of the balance sheet date.", "label": "Liabilities Total [Member]", "terseLabel": "Liabilities [Member]" } } }, "localname": "LiabilitiesTotalMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureConcentrationsOfCreditRiskAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_LicensingAgreementsMember": { "auth_ref": [ "r326" ], "lang": { "en-US": { "role": { "documentation": "Rights, generally of limited duration, under a license arrangement (for example, to sell or otherwise utilize specified products or processes in a specified territory).", "label": "Licensing Agreements [Member]", "terseLabel": "License Agreements (GSE) [Member]" } } }, "localname": "LicensingAgreementsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_LimitedPartnersCapitalAccountUnitsOutstanding": { "auth_ref": [ "r140", "r256" ], "lang": { "en-US": { "role": { "documentation": "The number of limited partner units outstanding.", "label": "Limited Partners Capital Account Units Outstanding", "terseLabel": "Limited partners capital account units held by BGC" } } }, "localname": "LimitedPartnersCapitalAccountUnitsOutstanding", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_LineOfCreditFacilityCapacityAvailableForSpecificPurposeOtherThanForTradePurchases": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.", "label": "Line Of Credit Facility Capacity Available For Specific Purpose Other Than For Trade Purchases", "terseLabel": "Lines available", "verboseLabel": "Warehouse facility available" } } }, "localname": "LineOfCreditFacilityCapacityAvailableForSpecificPurposeOtherThanForTradePurchases", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LineOfCreditFacilityDescription": { "auth_ref": [ "r33" ], "lang": { "en-US": { "role": { "documentation": "Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.", "label": "Line Of Credit Facility Description", "terseLabel": "Line of credit facility, description" } } }, "localname": "LineOfCreditFacilityDescription", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_LineOfCreditFacilityExpirationDate1": { "auth_ref": [ "r33" ], "lang": { "en-US": { "role": { "documentation": "Date the credit facility terminates, in CCYY-MM-DD format.", "label": "Line Of Credit Facility Expiration Date1", "terseLabel": "Credit agreement maturity date", "verboseLabel": "Warehouse facility extended maturity date" } } }, "localname": "LineOfCreditFacilityExpirationDate1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "dateItemType" }, "us-gaap_LineOfCreditFacilityIncreaseDecreaseForPeriodNet": { "auth_ref": [ "r119" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) of the credit facility.", "label": "Line Of Credit Facility Increase Decrease For Period Net", "terseLabel": "Warehouse facility increase (decrease)" } } }, "localname": "LineOfCreditFacilityIncreaseDecreaseForPeriodNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LineOfCreditFacilityInterestRateDescription": { "auth_ref": [ "r33" ], "lang": { "en-US": { "role": { "documentation": "Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).", "label": "Line Of Credit Facility Interest Rate Description", "terseLabel": "Line of credit facility, interest rate description" } } }, "localname": "LineOfCreditFacilityInterestRateDescription", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity": { "auth_ref": [ "r33" ], "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": "Maximum revolving credit" } } }, "localname": "LineOfCreditFacilityMaximumBorrowingCapacity", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_LoanOriginationCommitmentsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Commitments to borrowers or third party investors for the origination of a loan.", "label": "Loan Origination Commitments [Member]", "terseLabel": "Deliver Loans to Third-party Investors [Member]" } } }, "localname": "LoanOriginationCommitmentsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_LoansHeldForSaleFairValueDisclosure": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail": { "order": 10060.0, "parentTag": "us-gaap_AssetsFairValueDisclosure", "weight": 1.0 }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10310.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.", "label": "Loans Held For Sale Fair Value Disclosure", "positiveTerseLabel": "Loans held for sale", "terseLabel": "Loans held for sale, at fair value", "verboseLabel": "Loans held for sale, at fair value" } } }, "localname": "LoansHeldForSaleFairValueDisclosure", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LondonInterbankOfferedRateLIBORMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Interest rate at which a bank borrows funds from other banks in the London interbank market.", "label": "London Interbank Offered Rate L I B O R [Member]", "terseLabel": "LIBOR [Member]", "verboseLabel": "One Month LIBOR [Member]" } } }, "localname": "LondonInterbankOfferedRateLIBORMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "domainItemType" }, "us-gaap_LongTermDebtNoncurrent": { "auth_ref": [ "r44" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10140.0, "parentTag": "us-gaap_Liabilities", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.", "label": "Long Term Debt Noncurrent", "terseLabel": "Long-term debt", "verboseLabel": "Long-term debt" } } }, "localname": "LongTermDebtNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_LongTermDebtTerm": { "auth_ref": [ "r376" ], "lang": { "en-US": { "role": { "documentation": "Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.", "label": "Long Term Debt Term", "terseLabel": "Credit agreement maturity period" } } }, "localname": "LongTermDebtTerm", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "us-gaap_LongtermDebtTypeAxis": { "auth_ref": [ "r44" ], "lang": { "en-US": { "role": { "documentation": "Information by type of long-term debt.", "label": "Longterm Debt Type [Axis]", "terseLabel": "Long-term Debt, Type" } } }, "localname": "LongtermDebtTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_LongtermDebtTypeDomain": { "auth_ref": [ "r44", "r238" ], "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": "Longterm Debt Type [Domain]", "terseLabel": "Long-term Debt, Type" } } }, "localname": "LongtermDebtTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_LossContingenciesLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Loss Contingencies [Line Items]", "terseLabel": "Loss Contingencies [Line Items]" } } }, "localname": "LossContingenciesLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_LossContingenciesTable": { "auth_ref": [ "r221", "r222", "r223", "r224", "r225", "r226", "r227", "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.ngkf.com/20190930/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_LossContingencyAccrualAtCarryingValue": { "auth_ref": [ "r221" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of loss contingency liability.", "label": "Loss Contingency Accrual At Carrying Value", "terseLabel": "Contingent liability" } } }, "localname": "LossContingencyAccrualAtCarryingValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ManagingRisksInherentInServicingAssetsAndServicingLiabilitiesByTypeOfRiskAxis": { "auth_ref": [ "r448" ], "lang": { "en-US": { "role": { "documentation": "Information by type of risks inherent in servicing assets and servicing liabilities.", "label": "Managing Risks Inherent In Servicing Assets And Servicing Liabilities By Type Of Risk [Axis]", "terseLabel": "Servicing Assets and Servicing Liabilities Risk" } } }, "localname": "ManagingRisksInherentInServicingAssetsAndServicingLiabilitiesByTypeOfRiskAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_MarketableSecuritiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Marketable Securities [Abstract]" } } }, "localname": "MarketableSecuritiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_MarketableSecuritiesCurrent": { "auth_ref": [ "r3", "r36" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail": { "order": 10040.0, "parentTag": "us-gaap_AssetsFairValueDisclosure", "weight": 1.0 }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10300.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of investment in marketable security, classified as current.", "label": "Marketable Securities Current", "terseLabel": "Marketable securities" } } }, "localname": "MarketableSecuritiesCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_MarketableSecuritiesRealizedGainLoss": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10450.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).", "label": "Marketable Securities Realized Gain Loss", "negatedLabel": "Realized gains on marketable securities", "terseLabel": "Gain on sale of marketable securities" } } }, "localname": "MarketableSecuritiesRealizedGainLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_MarketableSecuritiesUnrealizedGainLoss": { "auth_ref": [ "r73" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10460.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of unrealized gain (loss) on investment in marketable security.", "label": "Marketable Securities Unrealized Gain Loss", "negatedLabel": "Unrealized gains on marketable securities", "terseLabel": "Marketable securities, unrealized gain (loss) on mark to market securities" } } }, "localname": "MarketableSecuritiesUnrealizedGainLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_MeasurementInputDiscountRateMember": { "auth_ref": [ "r374" ], "lang": { "en-US": { "role": { "documentation": "Measurement input using interest rate to determine present value of future cash flows.", "label": "Measurement Input Discount Rate [Member]", "terseLabel": "Measurement Input, Discount Rate [Member]" } } }, "localname": "MeasurementInputDiscountRateMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_MeasurementInputPriceVolatilityMember": { "auth_ref": [ "r374" ], "lang": { "en-US": { "role": { "documentation": "Measurement input using rate at which price of security will increase (decrease) for given set of returns.", "label": "Measurement Input Price Volatility [Member]", "terseLabel": "Volatility [Member]" } } }, "localname": "MeasurementInputPriceVolatilityMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_MeasurementInputTypeAxis": { "auth_ref": [ "r374" ], "lang": { "en-US": { "role": { "documentation": "Information by type of measurement input used to determine value of asset and liability.", "label": "Measurement Input Type [Axis]", "terseLabel": "Measurement Input Type" } } }, "localname": "MeasurementInputTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_MeasurementInputTypeDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Measurement input used to determine value of asset and liability.", "label": "Measurement Input Type [Domain]", "terseLabel": "Measurement Input Type" } } }, "localname": "MeasurementInputTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_MinorityInterest": { "auth_ref": [ "r54", "r480", "r504" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10060.0, "parentTag": "us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest", "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 is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).", "label": "Minority Interest", "terseLabel": "Noncontrolling interests", "verboseLabel": "Noncontrolling interests" } } }, "localname": "MinorityInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders": { "auth_ref": [ "r253" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.", "label": "Minority Interest Decrease From Distributions To Noncontrolling Interest Holders", "negatedLabel": "Earning distributions to limited partnership interests, redeemable partnership interests, and other noncontrolling interests" } } }, "localname": "MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_MortgageBankingAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Mortgage Banking [Abstract]" } } }, "localname": "MortgageBankingAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_MortgagesHeldForSaleFairValueDisclosure": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10230.0, "parentTag": "us-gaap_Assets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value portion of mortgage loans held-for-sale.", "label": "Mortgages Held For Sale Fair Value Disclosure", "terseLabel": "Mortgage servicing rights, net" } } }, "localname": "MortgagesHeldForSaleFairValueDisclosure", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetCashProvidedByUsedInFinancingActivities": { "auth_ref": [ "r97" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10030.0, "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect", "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 (used in) provided by financing activities" } } }, "localname": "NetCashProvidedByUsedInFinancingActivities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Net Cash Provided By Used In Financing Activities [Abstract]", "terseLabel": "CASH FLOWS FROM FINANCING ACTIVITIES:" } } }, "localname": "NetCashProvidedByUsedInFinancingActivitiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_NetCashProvidedByUsedInInvestingActivities": { "auth_ref": [ "r97" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10020.0, "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect", "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.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Net Cash Provided By Used In Investing Activities [Abstract]", "terseLabel": "CASH FLOWS FROM INVESTING ACTIVITIES:" } } }, "localname": "NetCashProvidedByUsedInInvestingActivitiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_NetCashProvidedByUsedInOperatingActivities": { "auth_ref": [ "r97", "r102", "r105" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10010.0, "parentTag": "us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect", "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 (used in) operating activities" } } }, "localname": "NetCashProvidedByUsedInOperatingActivities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Net Cash Provided By Used In Operating Activities [Abstract]", "terseLabel": "CASH FLOWS FROM OPERATING ACTIVITIES:" } } }, "localname": "NetCashProvidedByUsedInOperatingActivitiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_NetIncomeLoss": { "auth_ref": [ "r62", "r64", "r70", "r105", "r136", "r487", "r512" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.", "label": "Net Income Loss", "totalLabel": "Net income available to common stockholders" } } }, "localname": "NetIncomeLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetIncomeLossAttributableToNoncontrollingInterest": { "auth_ref": [ "r62", "r64", "r345", "r349" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10020.0, "parentTag": "us-gaap_NetIncomeLoss", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of Net Income (Loss) attributable to noncontrolling interest.", "label": "Net Income Loss Attributable To Noncontrolling Interest", "terseLabel": "Less: Net income attributable to noncontrolling interests" } } }, "localname": "NetIncomeLossAttributableToNoncontrollingInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic": { "auth_ref": [ "r124", "r126" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail": { "order": 10050.0, "parentTag": "us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.", "label": "Net Income Loss Available To Common Stockholders Basic", "terseLabel": "Net income available to common stockholders" } } }, "localname": "NetIncomeLossAvailableToCommonStockholdersBasic", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfBasicEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted": { "auth_ref": [ "r126", "r127" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.", "label": "Net Income Loss Available To Common Stockholders Diluted", "terseLabel": "Net income for fully diluted shares", "totalLabel": "Net income for fully diluted shares" } } }, "localname": "NetIncomeLossAvailableToCommonStockholdersDiluted", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Disclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact.", "label": "New Accounting Pronouncements Policy Policy [Text Block]", "terseLabel": "New Accounting Pronouncements" } } }, "localname": "NewAccountingPronouncementsPolicyPolicyTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationPolicies" ], "xbrltype": "textBlockItemType" }, "us-gaap_NoncompeteAgreementsMember": { "auth_ref": [ "r324" ], "lang": { "en-US": { "role": { "documentation": "Agreement in which one party agrees not to pursue a similar trade in competition with another party.", "label": "Noncompete Agreements [Member]", "terseLabel": "Non-compete Agreements [Member]" } } }, "localname": "NoncompeteAgreementsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_NoncontrollingInterestAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Noncontrolling Interest [Abstract]", "terseLabel": "Noncontrolling Interest [Abstract]" } } }, "localname": "NoncontrollingInterestAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable": { "auth_ref": [ "r78" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount after tax of income (loss) attributable to redeemable noncontrolling preferred unit holders.", "label": "Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable", "terseLabel": "Issuance of exchangeable preferred partnership units in Newmark OpCo" } } }, "localname": "NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance": { "auth_ref": [ "r254", "r343", "r347" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.", "label": "Noncontrolling Interest Increase From Subsidiary Equity Issuance", "terseLabel": "BGC's purchase of exchangeable limited partnership units in Newmark Holdings" } } }, "localname": "NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_NoncontrollingInterestMember": { "auth_ref": [ "r338" ], "lang": { "en-US": { "role": { "documentation": "This element represents that portion of equity (net assets) in a subsidiary not attributable, directly or indirectly, to the parent. A noncontrolling interest is sometimes called a minority interest.", "label": "Noncontrolling Interest [Member]", "terseLabel": "Noncontrolling Interests in Subsidiaries [Member]", "verboseLabel": "Limited Partnership Interests or Other Equity Interests in Subsidiaries [Member]" } } }, "localname": "NoncontrollingInterestMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "domainItemType" }, "us-gaap_NondesignatedMember": { "auth_ref": [ "r355" ], "lang": { "en-US": { "role": { "documentation": "Derivative instrument not designated as hedging instrument under Generally Accepted Accounting Principles (GAAP).", "label": "Nondesignated [Member]", "terseLabel": "Not Designated as Hedging Instrument [Member]" } } }, "localname": "NondesignatedMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_NotesPayableRelatedPartiesNoncurrent": { "auth_ref": [ "r45", "r120", "r428" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The amount for notes payable (written promise to pay), payable to related parties, which are due after one year (or one business cycle).", "label": "Notes Payable Related Parties Noncurrent", "verboseLabel": "Promissory Note" } } }, "localname": "NotesPayableRelatedPartiesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_NotesReceivableGross": { "auth_ref": [ "r179" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount, before allowance for credit loss, of financing receivable.", "label": "Notes Receivable Gross", "terseLabel": "Loans receivable, commercial real estate loan amount" } } }, "localname": "NotesReceivableGross", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_NumberOfOperatingSegments": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.", "label": "Number Of Operating Segments", "terseLabel": "Number of operating segment" } } }, "localname": "NumberOfOperatingSegments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" ], "xbrltype": "integerItemType" }, "us-gaap_OperatingIncomeLoss": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10050.0, "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 from operations" } } }, "localname": "OperatingIncomeLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseCost": { "auth_ref": [ "r417", "r424" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseIncomeComprehensiveIncomeExtensibleList": { "auth_ref": [ "r426" ], "lang": { "en-US": { "role": { "documentation": "Indicates line item in statement of comprehensive income that includes operating lease income.", "label": "Operating Lease Income Comprehensive Income Extensible List", "terseLabel": "Operating Lease, Income, Comprehensive Income [Extensible List]" } } }, "localname": "OperatingLeaseIncomeComprehensiveIncomeExtensibleList", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "extensibleListItemType" }, "us-gaap_OperatingLeaseLiability": { "auth_ref": [ "r411" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail2": { "order": 10020.0, "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": "Present value of lease liability", "verboseLabel": "ROU liability" } } }, "localname": "OperatingLeaseLiability", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesUnderTopic842Detail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseLiabilityCurrent": { "auth_ref": [ "r411" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": 10070.0, "parentTag": "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent", "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 ROU liabilities, current", "verboseLabel": "ROU liabilities" } } }, "localname": "OperatingLeaseLiabilityCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList": { "auth_ref": [ "r412" ], "lang": { "en-US": { "role": { "documentation": "Indicates line item in statement of financial position that includes current operating lease liability.", "label": "Operating Lease Liability Current Statement Of Financial Position Extensible List", "terseLabel": "Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]" } } }, "localname": "OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "extensibleListItemType" }, "us-gaap_OperatingLeaseLiabilityNoncurrent": { "auth_ref": [ "r411" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail": { "order": 10010.0, "parentTag": "us-gaap_OtherLiabilitiesNoncurrent", "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 ROU liabilities, non current", "verboseLabel": "ROU liabilities" } } }, "localname": "OperatingLeaseLiabilityNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList": { "auth_ref": [ "r412" ], "lang": { "en-US": { "role": { "documentation": "Indicates line item in statement of financial position that includes noncurrent operating lease liability.", "label": "Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List", "terseLabel": "Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]" } } }, "localname": "OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "extensibleListItemType" }, "us-gaap_OperatingLeasePayments": { "auth_ref": [ "r413", "r420" ], "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", "terseLabel": "Payments for operating lease liabilities" } } }, "localname": "OperatingLeasePayments", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseRightOfUseAsset": { "auth_ref": [ "r410" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail": { "order": 10010.0, "parentTag": "us-gaap_OtherAssetsNoncurrent", "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", "positiveLabel": "Operating lease ROU assets", "terseLabel": "ROU asset", "verboseLabel": "ROU Asset" } } }, "localname": "OperatingLeaseRightOfUseAsset", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList": { "auth_ref": [ "r412" ], "lang": { "en-US": { "role": { "documentation": "Indicates line item in statement of financial position that includes operating lease right-of-use asset.", "label": "Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List", "terseLabel": "Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]" } } }, "localname": "OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "extensibleListItemType" }, "us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent": { "auth_ref": [ "r422", "r424" ], "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": "Operating lease, weighted-average discount rate" } } }, "localname": "OperatingLeaseWeightedAverageDiscountRatePercent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1": { "auth_ref": [ "r421", "r424" ], "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 Term1", "terseLabel": "Operating lease, remaining weighted-average lease term" } } }, "localname": "OperatingLeaseWeightedAverageRemainingLeaseTerm1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "us-gaap_OperatingLeasesFutureMinimumPaymentsDue": { "auth_ref": [ "r405", "r407" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.", "label": "Operating Leases Future Minimum Payments Due", "totalLabel": "Total" } } }, "localname": "OperatingLeasesFutureMinimumPaymentsDue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears": { "auth_ref": [ "r405", "r407" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail": { "order": 10050.0, "parentTag": "us-gaap_OperatingLeasesFutureMinimumPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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": "Operating Leases Future Minimum Payments Due In Five Years", "terseLabel": "2023" } } }, "localname": "OperatingLeasesFutureMinimumPaymentsDueInFiveYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears": { "auth_ref": [ "r405", "r407" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail": { "order": 10040.0, "parentTag": "us-gaap_OperatingLeasesFutureMinimumPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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": "Operating Leases Future Minimum Payments Due In Four Years", "terseLabel": "2022" } } }, "localname": "OperatingLeasesFutureMinimumPaymentsDueInFourYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears": { "auth_ref": [ "r405", "r407" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail": { "order": 10030.0, "parentTag": "us-gaap_OperatingLeasesFutureMinimumPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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": "Operating Leases Future Minimum Payments Due In Three Years", "terseLabel": "2021" } } }, "localname": "OperatingLeasesFutureMinimumPaymentsDueInThreeYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears": { "auth_ref": [ "r405", "r407" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail": { "order": 10020.0, "parentTag": "us-gaap_OperatingLeasesFutureMinimumPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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": "Operating Leases Future Minimum Payments Due In Two Years", "terseLabel": "2020" } } }, "localname": "OperatingLeasesFutureMinimumPaymentsDueInTwoYears", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter": { "auth_ref": [ "r405", "r407" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail": { "order": 10060.0, "parentTag": "us-gaap_OperatingLeasesFutureMinimumPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after 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": "Operating Leases Future Minimum Payments Due Thereafter", "terseLabel": "Thereafter" } } }, "localname": "OperatingLeasesFutureMinimumPaymentsDueThereafter", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OperatingLeasesFutureMinimumPaymentsRemainderOfFiscalYear": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail": { "order": 10010.0, "parentTag": "us-gaap_OperatingLeasesFutureMinimumPaymentsDue", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the remainder of the 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": "Operating Leases Future Minimum Payments Remainder Of Fiscal Year", "terseLabel": "2019" } } }, "localname": "OperatingLeasesFutureMinimumPaymentsRemainderOfFiscalYear", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Organization Consolidation And Presentation Of Financial Statements [Abstract]" } } }, "localname": "OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock": { "auth_ref": [ "r0", "r352" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.", "label": "Organization Consolidation And Presentation Of Financial Statements Disclosure [Text Block]", "terseLabel": "Organization and Basis of Presentation" } } }, "localname": "OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentation" ], "xbrltype": "textBlockItemType" }, "us-gaap_OtherAssetsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Other Assets [Abstract]" } } }, "localname": "OtherAssetsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_OtherAssetsCurrent": { "auth_ref": [ "r55" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10340.0, "parentTag": "us-gaap_AssetsCurrent", "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 (see Note 19)", "totalLabel": "Total" } } }, "localname": "OtherAssetsCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherAssetsDisclosureTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for other assets. This disclosure includes other current assets and other noncurrent assets.", "label": "Other Assets Disclosure [Text Block]", "terseLabel": "Other Current and Non-current Assets" } } }, "localname": "OtherAssetsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssets" ], "xbrltype": "textBlockItemType" }, "us-gaap_OtherAssetsMiscellaneousCurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail": { "order": 10050.0, "parentTag": "us-gaap_OtherAssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of other miscellaneous assets expected to be realized or consumed within one year or operating cycle, if longer.", "label": "Other Assets Miscellaneous Current", "terseLabel": "Other" } } }, "localname": "OtherAssetsMiscellaneousCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherAssetsMiscellaneousNoncurrent": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail": { "order": 10060.0, "parentTag": "us-gaap_OtherAssetsNoncurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.", "label": "Other Assets Miscellaneous Noncurrent", "terseLabel": "Other" } } }, "localname": "OtherAssetsMiscellaneousNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherAssetsNoncurrent": { "auth_ref": [ "r31" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10270.0, "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 (see Note 19)", "totalLabel": "Total" } } }, "localname": "OtherAssetsNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfNonCurrentOtherAssetsDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherLiabilitiesNoncurrent": { "auth_ref": [ "r46" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10150.0, "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 (see Note 29)", "totalLabel": "Total" } } }, "localname": "OtherLiabilitiesNoncurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherLiabilitiesNoncurrentAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Other Liabilities Noncurrent [Abstract]" } } }, "localname": "OtherLiabilitiesNoncurrentAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_OtherNoncurrentAssetsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Primary financial statement caption encompassing other noncurrent assets.", "label": "Other Noncurrent Assets [Member]", "terseLabel": "Other Assets [Member]" } } }, "localname": "OtherNoncurrentAssetsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_OtherNoncurrentLiabilitiesMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Primary financial statement caption encompassing other noncurrent liabilities.", "label": "Other Noncurrent Liabilities [Member]", "terseLabel": "Other Long-Term Liabilities [Member]" } } }, "localname": "OtherNoncurrentLiabilitiesMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_OtherNoncurrentLiabilitiesTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of other noncurrent liabilities.", "label": "Other Noncurrent Liabilities Table [Text Block]", "terseLabel": "Components of Other long-term Liabilities" } } }, "localname": "OtherNoncurrentLiabilitiesTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_OtherOperatingActivitiesCashFlowStatement": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10500.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Other cash or noncash adjustments to reconcile net income to cash provided by (used in) operating activities that are not separately disclosed in the statement of cash flows (for example, cash received or cash paid during the current period for miscellaneous operating activities, net change during the reporting period in other assets or other liabilities).", "label": "Other Operating Activities Cash Flow Statement", "terseLabel": "Other" } } }, "localname": "OtherOperatingActivitiesCashFlowStatement", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_OtherOperatingIncomeExpenseMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Primary financial statement caption encompassing other operating income (expense).", "label": "Other Operating Income Expense [Member]", "terseLabel": "Other Income, Net [Member]", "verboseLabel": "Other Income, Net [Member]" } } }, "localname": "OtherOperatingIncomeExpenseMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_OtherOperatingIncomeExpenseNet": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10090.0, "parentTag": "us-gaap_OperatingIncomeLoss", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.", "label": "Other Operating Income Expense Net", "terseLabel": "Other income, net" } } }, "localname": "OtherOperatingIncomeExpenseNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_PartnerTypeOfPartnersCapitalAccountAxis": { "auth_ref": [ "r139", "r255" ], "lang": { "en-US": { "role": { "documentation": "Information by type or class of partner's capital account. Examples of classes of partners include, but not limited to, general partners, limited partners, preferred partners, and other ownership interests.", "label": "Partner Type Of Partners Capital Account [Axis]", "terseLabel": "Partner Type" } } }, "localname": "PartnerTypeOfPartnersCapitalAccountAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_PartnerTypeOfPartnersCapitalAccountNameDomain": { "auth_ref": [ "r139", "r256", "r523" ], "lang": { "en-US": { "role": { "documentation": "Capital accounts of each type or class of partner. Examples of classes of partners include, but are not limited to, general partners, limited partners, preferred partners, and other ownership interests.", "label": "Partner Type Of Partners Capital Account Name [Domain]", "terseLabel": "Partner Type of Partners' Capital Account, Name" } } }, "localname": "PartnerTypeOfPartnersCapitalAccountNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_PartnersCapitalAccountSaleOfUnits": { "auth_ref": [ "r253", "r256" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Total change in each class of partners' capital accounts during the year due to the sale of units. All partners include general, limited and preferred partners.", "label": "Partners Capital Account Sale Of Units", "terseLabel": "Purchase value of units" } } }, "localname": "PartnersCapitalAccountSaleOfUnits", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_PartnersCapitalAccountUnitsSaleOfUnits": { "auth_ref": [ "r141", "r253" ], "lang": { "en-US": { "role": { "documentation": "Total units issued during the year due to the sale of units. All partners include general, limited and preferred partners.", "label": "Partners Capital Account Units Sale Of Units", "terseLabel": "Purchase of units" } } }, "localname": "PartnersCapitalAccountUnitsSaleOfUnits", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_PartnersCapitalNotesDisclosureTextBlock": { "auth_ref": [ "r259" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for the formation, structure, control and ownership of the partnership. Disclosures related to accounts comprising partners' capital. Includes balances of general partners' capital account, limited partners' capital account, preferred partners' capital account and total partners' capital account and units outstanding; accumulated other comprehensive income; amount and nature of changes to amount of partner's capital and units outstanding by class, rights and privileges for each class of units; distribution policies and distributions paid by unit class; impact of and correction of an error in previously issued financial statements; limitations of partners' liability; redemption, conversion and distribution policies; and deferred compensation related to the issuance of units.", "label": "Partners Capital Notes Disclosure [Text Block]", "terseLabel": "Limited Partnership Interests" } } }, "localname": "PartnersCapitalNotesDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterests" ], "xbrltype": "textBlockItemType" }, "us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale": { "auth_ref": [ "r95", "r101" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10480.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The amount of cash paid for the origination of mortgages that are held for sale.", "label": "Payments For Origination Of Mortgage Loans Held For Sale", "negatedLabel": "Loan originations\u2014loans held for sale" } } }, "localname": "PaymentsForOriginationOfMortgageLoansHeldForSale", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsForRepurchaseOfCommonStock": { "auth_ref": [ "r90" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10170.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow to reacquire common stock during the period.", "label": "Payments For Repurchase Of Common Stock", "negatedLabel": "Treasury stock repurchases" } } }, "localname": "PaymentsForRepurchaseOfCommonStock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsForRepurchaseOfInitialPublicOffering": { "auth_ref": [ "r90" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10110.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow associated with the repurchase of amount received from entity's first offering of stock to the public.", "label": "Payments For Repurchase Of Initial Public Offering", "negatedLabel": "Fees relating to the IPO" } } }, "localname": "PaymentsForRepurchaseOfInitialPublicOffering", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsOfCapitalDistribution": { "auth_ref": [ "r90" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10160.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Cash outflow to owners or shareholders, excluding ordinary dividends. Includes special dividends.", "label": "Payments Of Capital Distribution", "negatedLabel": "Dividends to stockholders" } } }, "localname": "PaymentsOfCapitalDistribution", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsOfDividendsMinorityInterest": { "auth_ref": [ "r90" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10150.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of cash outflow in the form of ordinary dividends provided by the non-wholly owned subsidiary to noncontrolling interests.", "label": "Payments Of Dividends Minority Interest", "negatedLabel": "Earnings distributions to limited partnership interests and noncontrolling interests" } } }, "localname": "PaymentsOfDividendsMinorityInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsOfFinancingCosts": { "auth_ref": [ "r92" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10190.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow for loan and debt issuance costs.", "label": "Payments Of Financing Costs", "negatedLabel": "Payments of deferred financing costs" } } }, "localname": "PaymentsOfFinancingCosts", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsOfMergerRelatedCostsFinancingActivities": { "auth_ref": [ "r92" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10180.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow for financing costs associated with business combinations.", "label": "Payments Of Merger Related Costs Financing Activities", "negatedLabel": "Payments on acquisition earn-outs" } } }, "localname": "PaymentsOfMergerRelatedCostsFinancingActivities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired": { "auth_ref": [ "r84" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10200.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.", "label": "Payments To Acquire Businesses Net Of Cash Acquired", "negatedLabel": "Payments for acquisitions, net of cash acquired" } } }, "localname": "PaymentsToAcquireBusinessesNetOfCashAcquired", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsToAcquireMortgageServicingRightsMSR": { "auth_ref": [ "r86", "r445" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10250.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow to obtain servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. Rights may be obtained via (1) acquisition or assumption of a servicing obligation that does not relate to financial assets of the servicer or its consolidated affiliates; or (2) by originating mortgage loans and then (a) transferring the loans to a Variable Interest Entity (VIE) in a transaction that meets the necessary transfer and classification requirements, or (b) transferring the loans in a transaction that meets the requirements for sale accounting.", "label": "Payments To Acquire Mortgage Servicing Rights M S R", "negatedLabel": "Purchases of mortgage servicing rights" } } }, "localname": "PaymentsToAcquireMortgageServicingRightsMSR", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PaymentsToAcquirePropertyPlantAndEquipment": { "auth_ref": [ "r85" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10240.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.", "label": "Payments To Acquire Property Plant And Equipment", "negatedLabel": "Purchases of fixed assets" } } }, "localname": "PaymentsToAcquirePropertyPlantAndEquipment", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_PlanNameAxis": { "auth_ref": [ "r279", "r299" ], "lang": { "en-US": { "role": { "documentation": "Information by plan name for share-based payment arrangement.", "label": "Plan Name [Axis]", "terseLabel": "Plan Name" } } }, "localname": "PlanNameAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "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" } } }, "localname": "PlanNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_PortionAtFairValueFairValueDisclosureMember": { "auth_ref": [ "r387" ], "lang": { "en-US": { "role": { "documentation": "Measured at fair value for financial reporting purposes.", "label": "Portion At Fair Value Fair Value Disclosure [Member]", "terseLabel": "Fair Value Disclosure Item Amounts [Default]" } } }, "localname": "PortionAtFairValueFairValueDisclosureMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail" ], "xbrltype": "domainItemType" }, "us-gaap_PreferredStockDividendsIncomeStatementImpact": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of preferred stock dividends that is an adjustment to net income apportioned to common stockholders.", "label": "Preferred Stock Dividends Income Statement Impact", "terseLabel": "Reduction for dividends on preferred stock or units" } } }, "localname": "PreferredStockDividendsIncomeStatementImpact", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfBasicEarningsPerShareParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperationsParenthetical" ], "xbrltype": "monetaryItemType" }, "us-gaap_PreferredUnitsByNameAxis": { "auth_ref": [ "r140", "r255", "r523" ], "lang": { "en-US": { "role": { "documentation": "Information by type or class of preferred units or special units.", "label": "Preferred Units By Name [Axis]", "terseLabel": "Preferred Units by Name" } } }, "localname": "PreferredUnitsByNameAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_PreferredUnitsClassDomain": { "auth_ref": [ "r140", "r256" ], "lang": { "en-US": { "role": { "documentation": "Type or class of preferred units or special units.", "label": "Preferred Units Class [Domain]", "terseLabel": "Preferred Units, Class" } } }, "localname": "PreferredUnitsClassDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_PrepaidExpenseCurrent": { "auth_ref": [ "r4", "r7", "r190" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail": { "order": 10030.0, "parentTag": "us-gaap_OtherAssetsCurrent", "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.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_PrepaidTaxes": { "auth_ref": [ "r5", "r7", "r189", "r190" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail": { "order": 10020.0, "parentTag": "us-gaap_OtherAssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of asset related to consideration paid in advance for income and other taxes that provide economic benefits within a future period of one year or the normal operating cycle, if longer.", "label": "Prepaid Taxes", "terseLabel": "Prepaid taxes" } } }, "localname": "PrepaidTaxes", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsSummaryOfOtherCurrentAssetsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromDistributionsReceivedFromRealEstatePartnerships": { "auth_ref": [ "r82" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10210.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from earnings received from real estate partnerships.", "label": "Proceeds From Distributions Received From Real Estate Partnerships", "terseLabel": "Distributions from Real Estate LP" } } }, "localname": "ProceedsFromDistributionsReceivedFromRealEstatePartnerships", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromIssuanceOfDebt": { "auth_ref": [ "r88" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10130.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "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": "Borrowings of debt" } } }, "localname": "ProceedsFromIssuanceOfDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromIssuanceOfLongTermDebt": { "auth_ref": [ "r88" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.", "label": "Proceeds From Issuance Of Long Term Debt", "terseLabel": "Proceeds from debt" } } }, "localname": "ProceedsFromIssuanceOfLongTermDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromIssuanceOfPreferredLimitedPartnersUnits": { "auth_ref": [ "r87" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10070.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from the issuance of preferred limited partners units during the period.", "label": "Proceeds From Issuance Of Preferred Limited Partners Units", "terseLabel": "Limited partnership units issued", "verboseLabel": "Proceeds from issuance of exchangeable preferred partnership units" } } }, "localname": "ProceedsFromIssuanceOfPreferredLimitedPartnersUnits", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromLinesOfCredit": { "auth_ref": [ "r88", "r119" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10040.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.", "label": "Proceeds From Lines Of Credit", "terseLabel": "Proceeds from warehouse facilities", "verboseLabel": "Borrowings from credit agreement" } } }, "localname": "ProceedsFromLinesOfCredit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromPartnershipContribution": { "auth_ref": [ "r89" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10060.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from the capital received in cash from a partner in a partnership during the period.", "label": "Proceeds From Partnership Contribution", "terseLabel": "Proceeds from BGC's purchase of exchangeable limited partnership units in Newmark Holdings" } } }, "localname": "ProceedsFromPartnershipContribution", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromRelatedPartyDebt": { "auth_ref": [ "r88" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10090.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.", "label": "Proceeds From Related Party Debt", "terseLabel": "Borrowings from related parties" } } }, "localname": "ProceedsFromRelatedPartyDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities": { "auth_ref": [], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10220.0, "parentTag": "us-gaap_NetCashProvidedByUsedInInvestingActivities", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.", "label": "Proceeds From Sale And Maturity Of Marketable Securities", "terseLabel": "Proceeds from the sale of marketable securities", "verboseLabel": "Gross proceeds from sale of marketable securities" } } }, "localname": "ProceedsFromSaleAndMaturityOfMarketableSecurities", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale": { "auth_ref": [ "r95", "r98" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10490.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.", "label": "Proceeds From Sale Of Mortgage Loans Held For Sale", "terseLabel": "Loan sales\u2014loans held for sale" } } }, "localname": "ProceedsFromSaleOfMortgageLoansHeldForSale", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets": { "auth_ref": [ "r83" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.", "label": "Proceeds From Sales Of Business Affiliate And Productive Assets", "terseLabel": "Consideration received on sale of assets" } } }, "localname": "ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ProfitLoss": { "auth_ref": [ "r62", "r64", "r94", "r151", "r156", "r340", "r344", "r346", "r349", "r350" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10330.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome": { "order": 10030.0, "parentTag": "us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest", "weight": 1.0 }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10010.0, "parentTag": "us-gaap_NetIncomeLoss", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.", "label": "Profit Loss", "terseLabel": "Consolidated net income", "totalLabel": "Consolidated net income", "verboseLabel": "Consolidated net income" } } }, "localname": "ProfitLoss", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncome", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_PropertyPlantAndEquipmentAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Property Plant And Equipment [Abstract]" } } }, "localname": "PropertyPlantAndEquipmentAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_PropertyPlantAndEquipmentByTypeAxis": { "auth_ref": [ "r30", "r217" ], "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 By Type [Axis]", "terseLabel": "Property, Plant and Equipment, Type" } } }, "localname": "PropertyPlantAndEquipmentByTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "xbrltype": "stringItemType" }, "us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock": { "auth_ref": [ "r219" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, accounting policies and methodology, roll forwards, depreciation, depletion and amortization expense, including composite depreciation, accumulated depreciation, depletion and amortization expense, useful lives and method used, income statement disclosures, assets held for sale and public utility disclosures.", "label": "Property Plant And Equipment Disclosure [Text Block]", "terseLabel": "Fixed Assets, Net" } } }, "localname": "PropertyPlantAndEquipmentDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNet" ], "xbrltype": "textBlockItemType" }, "us-gaap_PropertyPlantAndEquipmentGross": { "auth_ref": [ "r29", "r215" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail": { "order": 10010.0, "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": "Fixed assets, gross" } } }, "localname": "PropertyPlantAndEquipmentGross", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "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]", "verboseLabel": "Property, Plant and Equipment [Line Items]" } } }, "localname": "PropertyPlantAndEquipmentLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "xbrltype": "stringItemType" }, "us-gaap_PropertyPlantAndEquipmentNet": { "auth_ref": [ "r12", "r13", "r217", "r507" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10250.0, "parentTag": "us-gaap_Assets", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.", "label": "Property Plant And Equipment Net", "terseLabel": "Fixed assets, net", "totalLabel": "Total" } } }, "localname": "PropertyPlantAndEquipmentNet", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_PropertyPlantAndEquipmentNetAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Property Plant And Equipment Net [Abstract]" } } }, "localname": "PropertyPlantAndEquipmentNetAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_PropertyPlantAndEquipmentTextBlock": { "auth_ref": [ "r12", "r217" ], "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 [Text Block]", "terseLabel": "Components of Fixed Assets, Net" } } }, "localname": "PropertyPlantAndEquipmentTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_PropertyPlantAndEquipmentTypeDomain": { "auth_ref": [ "r12", "r215" ], "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" } } }, "localname": "PropertyPlantAndEquipmentTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "xbrltype": "domainItemType" }, "us-gaap_ProvisionForDoubtfulAccounts": { "auth_ref": [ "r72", "r174" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10440.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of expense (reversal of expense) for expected credit loss on accounts receivable.", "label": "Provision For Doubtful Accounts", "terseLabel": "Provision for uncollectible accounts" } } }, "localname": "ProvisionForDoubtfulAccounts", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_RealEstateLoanMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Loan to finance the purchase of real estate, including but not limited to, land or building.", "label": "Real Estate Loan [Member]", "terseLabel": "Commercial Real Estate Loan [Member]" } } }, "localname": "RealEstateLoanMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_ReceivablesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Receivables [Abstract]" } } }, "localname": "ReceivablesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock": { "auth_ref": [ "r153", "r154" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of all significant reconciling items in the reconciliation of total revenues from reportable segments to the entity's consolidated revenues.", "label": "Reconciliation Of Revenue From Segments To Consolidated [Text Block]", "terseLabel": "Schedule of Recognized Revenues" } } }, "localname": "ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_RedeemableNoncontrollingInterestTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of redeemable noncontrolling interest (as defined) included in the statement of financial position as either a liability or temporary equity. As of the date of the statement of financial position, such redeemable noncontrolling interest is currently redeemable, as defined, for cash or other assets of the entity at (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the entity.", "label": "Redeemable Noncontrolling Interest Table [Text Block]", "terseLabel": "Schedule of Changes in Carrying Amount of Redeemable Partnership Interest" } } }, "localname": "RedeemableNoncontrollingInterestTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_RelatedPartyDomain": { "auth_ref": [ "r435" ], "lang": { "en-US": { "role": { "documentation": "Related parties include affiliates; other entities for which investments are accounted for by the equity method by the entity; trusts for benefit of employees; and principal owners, management, and members of immediate families. It also may include other parties with which the entity may control or can significantly influence the management or operating policies of the other to an extent that one of the transacting parties might be prevented from fully pursuing its own separate interests.", "label": "Related Party [Domain]", "terseLabel": "Related Party" } } }, "localname": "RelatedPartyDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails" ], "xbrltype": "domainItemType" }, "us-gaap_RelatedPartyTransactionAmountsOfTransaction": { "auth_ref": [ "r427", "r431", "r432" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of transactions with related party during the financial reporting period.", "label": "Related Party Transaction Amounts Of Transaction", "terseLabel": "Transaction agreement, distribution" } } }, "localname": "RelatedPartyTransactionAmountsOfTransaction", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_RelatedPartyTransactionAxis": { "auth_ref": [ "r274", "r429", "r431" ], "lang": { "en-US": { "role": { "documentation": "Information by type of related party transaction.", "label": "Related Party Transaction [Axis]", "terseLabel": "Related Party Transaction" } } }, "localname": "RelatedPartyTransactionAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_RelatedPartyTransactionDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Transaction between related party.", "label": "Related Party Transaction [Domain]", "terseLabel": "Related Party Transaction" } } }, "localname": "RelatedPartyTransactionDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_RelatedPartyTransactionDueFromToRelatedPartyAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Related Party Transaction Due From To Related Party [Abstract]" } } }, "localname": "RelatedPartyTransactionDueFromToRelatedPartyAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty": { "auth_ref": [ "r427" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10120.0, "parentTag": "us-gaap_CostsAndExpenses", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.", "label": "Related Party Transaction Expenses From Transactions With Related Party", "terseLabel": "Fees to related parties" } } }, "localname": "RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_RelatedPartyTransactionLineItems": { "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": "Related Party Transaction [Line Items]", "terseLabel": "Related Party Transaction [Line Items]" } } }, "localname": "RelatedPartyTransactionLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.", "label": "Related Party Transaction Other Revenues From Transactions With Related Party", "terseLabel": "Revenue from loan referral agreement" } } }, "localname": "RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_RelatedPartyTransactionsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Related Party Transactions [Abstract]" } } }, "localname": "RelatedPartyTransactionsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_RelatedPartyTransactionsByRelatedPartyAxis": { "auth_ref": [ "r274", "r429", "r431", "r462", "r463", "r464", "r465", "r466", "r467", "r468", "r469", "r470", "r471", "r472", "r473" ], "lang": { "en-US": { "role": { "documentation": "Information by type of related party. Related parties include, but not limited to, affiliates; other entities for which investments are accounted for by the equity method by the entity; trusts for benefit of employees; and principal owners, management, and members of immediate families. It also may include other parties with which the entity may control or can significantly influence the management or operating policies of the other to an extent that one of the transacting parties might be prevented from fully pursuing its own separate interests.", "label": "Related Party Transactions By Related Party [Axis]", "terseLabel": "Related Party" } } }, "localname": "RelatedPartyTransactionsByRelatedPartyAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails" ], "xbrltype": "stringItemType" }, "us-gaap_RelatedPartyTransactionsDisclosureTextBlock": { "auth_ref": [ "r435" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.", "label": "Related Party Transactions Disclosure [Text Block]", "terseLabel": "Related Party Transactions" } } }, "localname": "RelatedPartyTransactionsDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactions" ], "xbrltype": "textBlockItemType" }, "us-gaap_RepaymentsOfConvertibleDebt": { "auth_ref": [ "r91" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.", "label": "Repayments Of Convertible Debt", "terseLabel": "Repayments of convertible debt" } } }, "localname": "RepaymentsOfConvertibleDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_RepaymentsOfDebt": { "auth_ref": [ "r91" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10120.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.", "label": "Repayments Of Debt", "negatedLabel": "Repayment of debt" } } }, "localname": "RepaymentsOfDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_RepaymentsOfLinesOfCredit": { "auth_ref": [ "r91", "r119" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10050.0, "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", "negatedLabel": "Principal payments on warehouse facilities", "terseLabel": "Repayments of credit agreement" } } }, "localname": "RepaymentsOfLinesOfCredit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_RepaymentsOfLongTermDebt": { "auth_ref": [ "r91" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.", "label": "Repayments Of Long Term Debt", "terseLabel": "Repayments of debt", "verboseLabel": "Repayments of debt" } } }, "localname": "RepaymentsOfLongTermDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_RepaymentsOfRelatedPartyDebt": { "auth_ref": [ "r91" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10080.0, "parentTag": "us-gaap_NetCashProvidedByUsedInFinancingActivities", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The cash outflow for the payment of a long-term borrowing made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.", "label": "Repayments Of Related Party Debt", "negatedLabel": "Payments to related parties" } } }, "localname": "RepaymentsOfRelatedPartyDebt", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue": { "auth_ref": [ "r1", "r10", "r106", "r111" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10290.0, "parentTag": "us-gaap_AssetsCurrent", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.", "label": "Restricted Cash And Cash Equivalents At Carrying Value", "terseLabel": "Restricted cash and cash equivalents" } } }, "localname": "RestrictedCashAndCashEquivalentsAtCarryingValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_RestrictedStockMember": { "auth_ref": [ "r135" ], "lang": { "en-US": { "role": { "documentation": "Stock including a provision that prohibits sale or substantive sale of an equity instrument for a specified period of time or until specified performance conditions are met.", "label": "Restricted Stock [Member]", "terseLabel": "Restricted Stock [Member]" } } }, "localname": "RestrictedStockMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail" ], "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 R S U [Member]", "terseLabel": "Restricted Stock Units (RSUs) [Member]", "verboseLabel": "RSUs [Member]" } } }, "localname": "RestrictedStockUnitsRSUMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail" ], "xbrltype": "domainItemType" }, "us-gaap_RetainedEarningsAccumulatedDeficit": { "auth_ref": [ "r23", "r253", "r503" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10100.0, "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": "Retained earnings" } } }, "localname": "RetainedEarningsAccumulatedDeficit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "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": "Retained Earnings [Member]" } } }, "localname": "RetainedEarningsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "domainItemType" }, "us-gaap_RevenueFromContractWithCustomerAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Revenue From Contract With Customer [Abstract]" } } }, "localname": "RevenueFromContractWithCustomerAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax": { "auth_ref": [ "r262", "r263" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail": { "order": 10010.0, "parentTag": "us-gaap_Revenues", "weight": 1.0 }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10160.0, "parentTag": "us-gaap_Revenues", "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": "Revenues" } } }, "localname": "RevenueFromContractWithCustomerExcludingAssessedTax", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "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": "Revenues from Contracts with Customers" } } }, "localname": "RevenueFromContractWithCustomerTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomers" ], "xbrltype": "textBlockItemType" }, "us-gaap_RevenueFromRelatedParties": { "auth_ref": [ "r77", "r526" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.", "label": "Revenue From Related Parties", "terseLabel": "Recognized related party revenues" } } }, "localname": "RevenueFromRelatedParties", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_Revenues": { "auth_ref": [ "r67", "r147", "r148", "r155" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail": { "order": null, "parentTag": null, "root": true, "weight": null }, "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations": { "order": 10070.0, "parentTag": "us-gaap_OperatingIncomeLoss", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).", "label": "Revenues", "terseLabel": "Revenues", "totalLabel": "Revenues" } } }, "localname": "Revenues", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRecognizedRevenuesDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "monetaryItemType" }, "us-gaap_RevenuesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Revenues [Abstract]", "terseLabel": "Revenues:" } } }, "localname": "RevenuesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "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 [Member]", "verboseLabel": "Credit Facility [Member]" } } }, "localname": "RevolvingCreditFacilityMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtDetail" ], "xbrltype": "domainItemType" }, "us-gaap_RisksAndUncertaintiesAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Risks And Uncertainties [Abstract]" } } }, "localname": "RisksAndUncertaintiesAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_RisksInherentInServicingAssetsAndServicingLiabilitiesTypeDomain": { "auth_ref": [ "r448" ], "lang": { "en-US": { "role": { "documentation": "The nature of risks inherent in servicing assets and servicing liabilities.", "label": "Risks Inherent In Servicing Assets And Servicing Liabilities Type [Domain]", "terseLabel": "Risks Inherent in Servicing Assets and Servicing Liabilities, Type" } } }, "localname": "RisksInherentInServicingAssetsAndServicingLiabilitiesTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_SaleOfStockNameOfTransactionDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Sale of the entity's stock, including, but not limited to, initial public offering (IPO) and private placement.", "label": "Sale Of Stock Name Of Transaction [Domain]", "terseLabel": "Sale of Stock" } } }, "localname": "SaleOfStockNameOfTransactionDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.", "label": "Sale Of Stock Number Of Shares Issued In Transaction", "terseLabel": "Shares received from transaction" } } }, "localname": "SaleOfStockNumberOfSharesIssuedInTransaction", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_SaleOfStockPricePerShare": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.", "label": "Sale Of Stock Price Per Share", "terseLabel": "Closing price per share" } } }, "localname": "SaleOfStockPricePerShare", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "perShareItemType" }, "us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable": { "auth_ref": [ "r52" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLoansHeldForSaleAtFairValueSummaryOfLoansHeldForSaleAtCostBasisAndFairValueDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable": { "auth_ref": [ "r135" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable": { "auth_ref": [ "r316", "r317" ], "lang": { "en-US": { "role": { "documentation": "Schedule reflecting each material business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities.", "label": "Schedule Of Business Acquisitions By Acquisition [Table]", "terseLabel": "Schedule Of Business Acquisitions By Acquisition [Table]" } } }, "localname": "ScheduleOfBusinessAcquisitionsByAcquisitionTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsSummaryOfComponentsOfPurchaseConsiderationTransferredAndPreliminaryAllocationOfAssetsAcquiredAndLiabilitiesAssumedDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfCommonStockOutstandingRollForwardTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the change in common stock outstanding.", "label": "Schedule Of Common Stock Outstanding Roll Forward Table [Text Block]", "terseLabel": "Schedule of Changes in Common Stock Outstanding" } } }, "localname": "ScheduleOfCommonStockOutstandingRollForwardTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable": { "auth_ref": [ "r496", "r498", "r499", "r500" ], "lang": { "en-US": { "role": { "documentation": "A table disclosing the capital amounts and ratios as of the balance sheet date indicating whether the entity or entities are in compliance with regulatory capital requirements, by entity.", "label": "Schedule Of Compliance With Regulatory Capital Requirements Under Banking Regulations [Table]", "terseLabel": "Schedule Of Compliance With Regulatory Capital Requirements Under Banking Regulations [Table]" } } }, "localname": "ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfDebtTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of information pertaining to short-term and long-debt instruments or arrangements, including but not limited to identification of terms, features, collateral requirements and other information necessary to a fair presentation.", "label": "Schedule Of Debt Table [Text Block]", "terseLabel": "Long-Term Debt" } } }, "localname": "ScheduleOfDebtTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfDerivativeInstrumentsGainLossInStatementOfFinancialPerformanceTextBlock": { "auth_ref": [ "r357", "r363", "r366" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the location and amount of derivative instruments and nonderivative instruments designated as hedging instruments reported before netting adjustments, and the amount of gain (loss) on derivative instruments and nonderivative instruments designated and qualified as hedging instruments.", "label": "Schedule Of Derivative Instruments Gain Loss In Statement Of Financial Performance [Text Block]", "terseLabel": "Gain (Loss) on Change in Fair Value of Derivatives Included on Condensed Consolidated Statements of Operations" } } }, "localname": "ScheduleOfDerivativeInstrumentsGainLossInStatementOfFinancialPerformanceTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock": { "auth_ref": [ "r362" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position.", "label": "Schedule Of Derivative Instruments In Statement Of Financial Position Fair Value [Text Block]", "terseLabel": "Fair Value of Derivative Contracts" } } }, "localname": "ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTextBlock": { "auth_ref": [ "r128", "r130", "r134", "r137" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the effect of income (loss) on basic earnings per share.", "label": "Schedule Of Earnings Per Share Basic By Common Class [Text Block]", "terseLabel": "Calculation of Basic Earnings Per Share" } } }, "localname": "ScheduleOfEarningsPerShareBasicByCommonClassTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTextBlock": { "auth_ref": [ "r79", "r128", "r130", "r131", "r134", "r137" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the effect of income (loss) on an entity's diluted earnings per share.", "label": "Schedule Of Earnings Per Share Diluted By Common Class [Text Block]", "terseLabel": "Calculation of Fully Diluted Earnings Per Share" } } }, "localname": "ScheduleOfEarningsPerShareDilutedByCommonClassTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfEquityMethodInvestmentsLineItems": { "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": "Schedule Of Equity Method Investments [Line Items]", "terseLabel": "Investment [Line Items]" } } }, "localname": "ScheduleOfEquityMethodInvestmentsLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfEquityMethodInvestmentsTable": { "auth_ref": [ "r171" ], "lang": { "en-US": { "role": { "documentation": "Summarization of information required and determined to be disclosed concerning equity method investments in common stock. The summarized information includes: (a) the name of each investee or group of investees for which combined disclosure is appropriate, (2) the percentage ownership of common stock, (3) the difference, if any, between the carrying amount of an investment and the value of the underlying equity in the net assets and the accounting treatment of difference, if any, and (4) the aggregate value of each identified investment based on its quoted market price, if available.", "label": "Schedule Of Equity Method Investments [Table]", "terseLabel": "Schedule Of Equity Method Investments [Table]" } } }, "localname": "ScheduleOfEquityMethodInvestmentsTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock": { "auth_ref": [ "r371", "r372" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).", "label": "Schedule Of Fair Value Assets And Liabilities Measured On Recurring Basis Table [Text Block]", "terseLabel": "Fair Value Hierarchy of Financial Assets and Liabilities under U.S. GAAP Guidance" } } }, "localname": "ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock": { "auth_ref": [ "r408" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of future minimum payments required in the aggregate and for each of the five succeeding fiscal years for operating leases having initial or remaining noncancelable lease terms in excess of one year and the total minimum rentals to be received in the future under noncancelable subleases as of the balance sheet date.", "label": "Schedule Of Future Minimum Rental Payments For Operating Leases Table [Text Block]", "terseLabel": "Schedule of Future Minimum Rental Payments for Operating Leases" } } }, "localname": "ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfGoodwillTextBlock": { "auth_ref": [ "r197", "r199" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.", "label": "Schedule Of Goodwill [Text Block]", "terseLabel": "Summary of Changes in Carrying Amount of Goodwill" } } }, "localname": "ScheduleOfGoodwillTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfGuaranteeObligationsTable": { "auth_ref": [ "r235" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure about the type or nature of guarantees, for example performance, indemnification, payment and other guarantees, and related information such as term, origin and purpose, triggering event, maximum exposure, and carrying value. Represents the guarantor's disclosures which include the information about each guarantee, or each group of similar guarantees, even if the likelihood of the guarantor's need to make any payments under the guarantee is remote. This excludes disclosures for product warranties.", "label": "Schedule Of Guarantee Obligations [Table]", "terseLabel": "Schedule Of Guarantee Obligations [Table]" } } }, "localname": "ScheduleOfGuaranteeObligationsTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfGuaranteeObligationsTextBlock": { "auth_ref": [ "r235", "r236" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of each guarantee obligation, or each group of similar guarantee obligations, including (a) the nature of the guarantee, including its term, how it arose, and the events or circumstances that would require the guarantor to perform under the guarantee; (b) the maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee; (c) the current carrying amount of the liability, if any, for the guarantor's obligations under the guarantee; and (d) the nature of any recourse provisions under the guarantee, and any assets held either as collateral or by third parties, and any relevant related party disclosure. Excludes disclosures about product warranties.", "label": "Schedule Of Guarantee Obligations [Text Block]", "terseLabel": "Summary of Changes in Estimated Liability Under Guarantee Liability" } } }, "localname": "ScheduleOfGuaranteeObligationsTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFinancialGuaranteeLiabilityTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock": { "auth_ref": [ "r197" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of goodwill and intangible assets, which may be broken down by segment or major class.", "label": "Schedule Of Intangible Assets And Goodwill Table [Text Block]", "terseLabel": "Components of Other Intangible Assets" } } }, "localname": "ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfLineOfCreditFacilitiesTextBlock": { "auth_ref": [ "r33", "r118" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of 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": "Schedule Of Line Of Credit Facilities [Text Block]", "terseLabel": "Schedule of Company Lines Available and Borrowings Outstanding" } } }, "localname": "ScheduleOfLineOfCreditFacilitiesTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock": { "auth_ref": [ "r31" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of noncurrent assets.", "label": "Schedule Of Other Assets Noncurrent [Text Block]", "terseLabel": "Summary of Non-current Other Assets" } } }, "localname": "ScheduleOfOtherAssetsNoncurrentTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfOtherCurrentAssetsTableTextBlock": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the carrying amounts of other current assets.", "label": "Schedule Of Other Current Assets Table [Text Block]", "terseLabel": "Summary of Other Current Assets" } } }, "localname": "ScheduleOfOtherCurrentAssetsTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOtherCurrentAndNonCurrentAssetsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfPropertyPlantAndEquipmentTable": { "auth_ref": [ "r30", "r217" ], "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": "Schedule Of Property Plant And Equipment [Table]", "terseLabel": "Schedule Of Property Plant And Equipment [Table]" } } }, "localname": "ScheduleOfPropertyPlantAndEquipmentTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock": { "auth_ref": [ "r321" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of the amounts recognized as of the acquisition date for each major class of assets acquired and liabilities assumed. May include but not limited to the following: (a) acquired receivables; (b) contingencies recognized at the acquisition date; and (c) the fair value of noncontrolling interests in the acquiree.", "label": "Schedule Of Recognized Identified Assets Acquired And Liabilities Assumed Table [Text Block]", "terseLabel": "Summary of Components of Purchase Consideration Transferred and Preliminary Allocation of Assets Acquired and Liabilities Assumed" } } }, "localname": "ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable": { "auth_ref": [ "r115", "r429", "r431", "r432", "r433", "r434" ], "lang": { "en-US": { "role": { "documentation": "Schedule of quantitative and qualitative information pertaining to related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.", "label": "Schedule Of Related Party Transactions By Related Party [Table]", "terseLabel": "Schedule Of Related Party Transactions By Related Party [Table]" } } }, "localname": "ScheduleOfRelatedPartyTransactionsByRelatedPartyTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfServicingAssetsAtAmortizedValueTextBlock": { "auth_ref": [ "r455" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of activity in the balance of servicing assets subsequently measured at amortized cost. Includes, but is not limited to, beginning and ending balances, additions, disposals, and amortization.", "label": "Schedule Of Servicing Assets At Amortized Value [Text Block]", "terseLabel": "Summary of Changes in the Carrying Amount of Mortgage Servicing Rights" } } }, "localname": "ScheduleOfServicingAssetsAtAmortizedValueTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfShareBasedCompensationActivityTableTextBlock": { "auth_ref": [ "r289", "r294", "r295" ], "lang": { "en-US": { "role": { "documentation": "Tabular disclosure of activity for award under share-based payment arrangement. Includes, but is not limited to, outstanding award at beginning and end of year, granted, exercised, forfeited, and weighted-average grant date fair value.", "label": "Schedule Of Share Based Compensation Activity Table [Text Block]", "terseLabel": "Activity Associated with Limited Partnership Units" } } }, "localname": "ScheduleOfShareBasedCompensationActivityTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable": { "auth_ref": [ "r279", "r299" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock": { "auth_ref": [ "r283" ], "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": "Schedule Of Share Based Compensation Restricted Stock Units Award Activity Table [Text Block]", "terseLabel": "Activity Associated with Restricted Stock Units" } } }, "localname": "ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_ScheduleOfStockByClassTable": { "auth_ref": [ "r50", "r117", "r240", "r241", "r242", "r244", "r245", "r246", "r250", "r251", "r252", "r253" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock": { "auth_ref": [ "r207" ], "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": "Scheduleof Finite Lived Intangible Assets Future Amortization Expense Table [Text Block]", "terseLabel": "Estimated Future Amortization Expense of Definite Life Intangible Assets" } } }, "localname": "ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetTables" ], "xbrltype": "textBlockItemType" }, "us-gaap_SecuritiesFinancingTransactionAxis": { "auth_ref": [ "r58", "r121", "r444" ], "lang": { "en-US": { "role": { "documentation": "Information by type of securities financing transactions, including, but not limited to those measured at fair value or cost.", "label": "Securities Financing Transaction [Axis]", "terseLabel": "Securities Financing Transaction" } } }, "localname": "SecuritiesFinancingTransactionAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_SecuritiesFinancingTransactionFairValueMember": { "auth_ref": [ "r444" ], "lang": { "en-US": { "role": { "documentation": "Measurement at fair value of security or securities involved in financing transaction.", "label": "Securities Financing Transaction Fair Value [Member]", "terseLabel": "Securities Financing Transaction, Fair Value [Member]" } } }, "localname": "SecuritiesFinancingTransactionFairValueMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_SecuritiesFinancingTransactionLineItems": { "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": "Securities Financing Transaction [Line Items]", "terseLabel": "Securities Financing Transaction [Line Items]" } } }, "localname": "SecuritiesFinancingTransactionLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "stringItemType" }, "us-gaap_SecuritiesFinancingTransactionTable": { "auth_ref": [ "r444" ], "lang": { "en-US": { "role": { "documentation": "Schedule, as of the balance sheet date, of security financing transactions by type, the aggregate value of securities financing transactions by type and aggregate acquisition price by type of security financing transaction.", "label": "Securities Financing Transaction [Table]", "terseLabel": "Securities Financing Transaction [Table]" } } }, "localname": "SecuritiesFinancingTransactionTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "stringItemType" }, "us-gaap_SecuritiesFinancingTransactionTypeDomain": { "auth_ref": [ "r444" ], "lang": { "en-US": { "role": { "documentation": "Measurement of financing transaction securities held.", "label": "Securities Financing Transaction Type [Domain]", "terseLabel": "Securities Financing Transaction" } } }, "localname": "SecuritiesFinancingTransactionTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_SecuritiesFinancingTransactionsDisclosuresAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Securities Financing Transactions Disclosures [Abstract]" } } }, "localname": "SecuritiesFinancingTransactionsDisclosuresAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_SecuritiesLoaned": { "auth_ref": [ "r59", "r60", "r443" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10190.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.", "label": "Securities Loaned", "terseLabel": "Securities loaned" } } }, "localname": "SecuritiesLoaned", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSecuritiesLoanedAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_SecurityDeposit": { "auth_ref": [ "r56" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.", "label": "Security Deposit", "terseLabel": "Deposit in Fannie Mae restricted liquidity account" } } }, "localname": "SecurityDeposit", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_SecurityDepositLiability": { "auth_ref": [ "r509" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail": { "order": 10050.0, "parentTag": "us-gaap_OtherLiabilitiesNoncurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "This element represents money paid in advance to protect the provider of a product or service, such as a lessor, against damage or nonpayment by the buyer or tenant (lessee) during the term of the agreement. Such damages may include physical damage to the property, theft of property, and other contractual breaches. Security deposits held may be interest or noninterest bearing.", "label": "Security Deposit Liability", "terseLabel": "Deposit in Fannie Mae restricted liquidity account", "verboseLabel": "Credit enhancement deposit" } } }, "localname": "SecurityDepositLiability", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfOtherLiabilitiesDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCreditEnhancementReceivableContingentLiabilityAndCreditEnhancementDepositAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_SegmentReportingAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Segment Reporting [Abstract]" } } }, "localname": "SegmentReportingAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_SegmentReportingPolicyPolicyTextBlock": { "auth_ref": [ "r112" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of accounting policy for segment reporting.", "label": "Segment Reporting Policy Policy [Text Block]", "terseLabel": "Segment" } } }, "localname": "SegmentReportingPolicyPolicyTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationPolicies" ], "xbrltype": "textBlockItemType" }, "us-gaap_ServicingAsset": { "auth_ref": [ "r447" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.", "label": "Servicing Asset", "terseLabel": "Servicing rights of loans originated", "totalLabel": "Net balance" } } }, "localname": "ServicingAsset", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ServicingAssetAtAmortizedValue": { "auth_ref": [ "r445", "r446", "r447", "r456" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail": { "order": 10010.0, "parentTag": "us-gaap_ServicingAsset", "weight": 1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.", "label": "Servicing Asset At Amortized Value", "periodEndLabel": "Ending Balance", "periodStartLabel": "Beginning Balance" } } }, "localname": "ServicingAssetAtAmortizedValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ServicingAssetAtAmortizedValueAdditions": { "auth_ref": [ "r457" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.", "label": "Servicing Asset At Amortized Value Additions", "terseLabel": "Additions" } } }, "localname": "ServicingAssetAtAmortizedValueAdditions", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ServicingAssetAtAmortizedValueAmortization1": { "auth_ref": [ "r458" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.", "label": "Servicing Asset At Amortized Value Amortization1", "negatedLabel": "Amortization" } } }, "localname": "ServicingAssetAtAmortizedValueAmortization1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ServicingAssetAtAmortizedValueBalanceRollForward": { "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": "Servicing Asset At Amortized Value Balance Roll Forward", "terseLabel": "Mortgage Servicing Rights" } } }, "localname": "ServicingAssetAtAmortizedValueBalanceRollForward", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ServicingAssetAtFairValueAdditions": { "auth_ref": [ "r453" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.", "label": "Servicing Asset At Fair Value Additions", "terseLabel": "Purchase of loans originated" } } }, "localname": "ServicingAssetAtFairValueAdditions", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ServicingAssetAtFairValueAmount": { "auth_ref": [ "r447", "r452" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.", "label": "Servicing Asset At Fair Value Amount", "verboseLabel": "Estimated fair value of MSRs" } } }, "localname": "ServicingAssetAtFairValueAmount", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ServicingAssetAtFairValuePeriodIncreaseDecrease": { "auth_ref": [ "r451" ], "lang": { "en-US": { "role": { "documentation": "The increase (decrease) in the fair value of servicing assets that are subsequently measured at fair value.", "label": "Servicing Asset At Fair Value Period Increase Decrease", "terseLabel": "Decrease in fair value of servicing rights" } } }, "localname": "ServicingAssetAtFairValuePeriodIncreaseDecrease", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate": { "auth_ref": [ "r450" ], "lang": { "en-US": { "role": { "documentation": "Discount rate used to estimate the fair value of servicing assets and servicing liabilities.", "label": "Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate", "terseLabel": "Discount rate" } } }, "localname": "ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "us-gaap_ServicingAssetsAtAmortizedValueLineItems": { "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": "Servicing Assets At Amortized Value [Line Items]", "terseLabel": "Servicing Assets At Amortized Value [Line Items]" } } }, "localname": "ServicingAssetsAtAmortizedValueLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ServicingAssetsAtAmortizedValueTable": { "auth_ref": [ "r455" ], "lang": { "en-US": { "role": { "documentation": "Disclosure of information about activity in the balance of servicing assets subsequently measured at amortized cost. Includes, but is not limited to, beginning and ending balances, additions, disposals, and amortization.", "label": "Servicing Assets At Amortized Value [Table]", "terseLabel": "Servicing Assets At Amortized Value [Table]" } } }, "localname": "ServicingAssetsAtAmortizedValueTable", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1": { "auth_ref": [ "r280" ], "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 Period1", "terseLabel": "Restricted shares, restriction period" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "durationItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue": { "auth_ref": [ "r293" ], "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": "Forfeited units" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail" ], "xbrltype": "perShareItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue": { "auth_ref": [ "r291" ], "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", "terseLabel": "Granted" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail" ], "xbrltype": "perShareItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber": { "auth_ref": [ "r290" ], "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", "terseLabel": "Number of unvested limited partnership units with post-termination pay-out" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue": { "auth_ref": [ "r290" ], "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": "Balance at the end of period", "periodStartLabel": "Balance at the beginning of period" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail" ], "xbrltype": "perShareItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms": { "auth_ref": [ "r296" ], "lang": { "en-US": { "role": { "documentation": "Weighted average remaining contractual term for equity-based awards excluding options, 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 Equity Instruments Other Than Options Outstanding Weighted Average Remaining Contractual Terms", "terseLabel": "Weighted-Average Remaining Contractual Term (Years)" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail" ], "xbrltype": "durationItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue": { "auth_ref": [ "r292" ], "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": "Settled units (delivered shares)" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail" ], "xbrltype": "perShareItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.", "label": "Share Based Compensation Arrangement By Share Based Payment Award [Line Items]", "terseLabel": "Share-based Compensation Arrangement by Share-based Payment Award [Line Items]" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised": { "auth_ref": [ "r287" ], "lang": { "en-US": { "role": { "documentation": "Number of non-option equity instruments exercised by participants.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Exercised", "negatedLabel": "Number of Settled units (delivered shares)" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeitures": { "auth_ref": [ "r288" ], "lang": { "en-US": { "role": { "documentation": "Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Forfeitures", "negatedLabel": "Number of Units, Forfeited units" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeitures", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted": { "auth_ref": [ "r286" ], "lang": { "en-US": { "role": { "documentation": "Net number of non-option equity instruments granted to participants.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Granted", "terseLabel": "Number of Units, Granted", "verboseLabel": "Awards granted" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOther": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Other increase (decrease) in number of shares reserved for issuance under non-option equity instrument agreements that is not separately disclosed.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Other", "terseLabel": "Number of Units, Other" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOther", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber": { "auth_ref": [ "r284", "r285" ], "lang": { "en-US": { "role": { "documentation": "Number of equity instruments other than options outstanding, including both vested and non-vested instruments.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding Number", "periodEndLabel": "Number of Units, Balance outstanding at end of period", "periodStartLabel": "Number of Units, Balance outstanding at beginning of period", "verboseLabel": "Limited partnership units outstanding" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithLimitedPartnershipUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationSummaryOfActivityOfNumberOfShareEquivalentLimitedPartnershipUnitsAndPostIPOGrantsDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized": { "auth_ref": [ "r281" ], "lang": { "en-US": { "role": { "documentation": "Number of shares authorized for issuance under share-based payment arrangement.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized", "terseLabel": "Shares authorized to be delivered pursuant to awards granted" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant": { "auth_ref": [ "r299" ], "lang": { "en-US": { "role": { "documentation": "The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant", "terseLabel": "Shares authorized to be delivered allowed for grant of future awards" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod": { "auth_ref": [ "r299" ], "lang": { "en-US": { "role": { "documentation": "Number of shares issued under share-based payment arrangement.", "label": "Share Based Compensation Arrangement By Share Based Payment Award Shares Issued In Period", "terseLabel": "Shares granted during period" } } }, "localname": "ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain": { "auth_ref": [ "r277", "r282" ], "lang": { "en-US": { "role": { "documentation": "Award under share-based payment arrangement.", "label": "Share Based Compensation Arrangements By Share Based Payment Award Award Type And Plan Name [Domain]", "terseLabel": "Award Type" } } }, "localname": "ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationActivityAssociatedWithRestrictedStockUnitsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail" ], "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", "terseLabel": "Stock price per share" } } }, "localname": "SharePrice", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "perShareItemType" }, "us-gaap_ShortTermLeaseCost": { "auth_ref": [ "r418", "r424" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount of short-term lease cost, excluding expense for lease with term of one month or less.", "label": "Short Term Lease Cost", "terseLabel": "Short-term lease expense" } } }, "localname": "ShortTermLeaseCost", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_SignificantAccountingPoliciesTextBlock": { "auth_ref": [ "r122" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for all significant accounting policies of the reporting entity.", "label": "Significant Accounting Policies [Text Block]", "terseLabel": "Summary of Significant Accounting Policies" } } }, "localname": "SignificantAccountingPoliciesTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSummaryOfSignificantAccountingPolicies" ], "xbrltype": "textBlockItemType" }, "us-gaap_SoftwareAndSoftwareDevelopmentCostsMember": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Purchased software applications and internally developed software for sale, licensing or long-term internal use.", "label": "Software And Software Development Costs [Member]", "terseLabel": "Software, Including Software Development Costs [Member]" } } }, "localname": "SoftwareAndSoftwareDevelopmentCostsMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFixedAssetsNetComponentsOfFixedAssetsNetDetail" ], "xbrltype": "domainItemType" }, "us-gaap_StatementClassOfStockAxis": { "auth_ref": [ "r17", "r18", "r19", "r243" ], "lang": { "en-US": { "role": { "documentation": "Information by the different classes of stock of the entity.", "label": "Statement Class Of Stock [Axis]", "terseLabel": "Class of Stock" } } }, "localname": "StatementClassOfStockAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCompensationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLimitedPartnershipInterestsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail", "http://www.ngkf.com/20190930/taxonomy/role/DocumentDocumentAndEntityInformation", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "stringItemType" }, "us-gaap_StatementEquityComponentsAxis": { "auth_ref": [ "r51", "r243" ], "lang": { "en-US": { "role": { "documentation": "Information by component of equity.", "label": "Statement Equity Components [Axis]", "terseLabel": "Equity Components" } } }, "localname": "StatementEquityComponentsAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "stringItemType" }, "us-gaap_StatementOfCashFlowsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statement Of Cash Flows [Abstract]" } } }, "localname": "StatementOfCashFlowsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_StatementOfFinancialPositionAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statement Of Financial Position [Abstract]" } } }, "localname": "StatementOfFinancialPositionAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statement Of Income And Comprehensive Income [Abstract]" } } }, "localname": "StatementOfIncomeAndComprehensiveIncomeAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_StatementOfPartnersCapitalAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Statement Of Partners Capital [Abstract]" } } }, "localname": "StatementOfPartnersCapitalAbstract", "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.ngkf.com/20190930/taxonomy/role/DisclosureCompensationTables", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "stringItemType" }, "us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation": { "auth_ref": [ "r276", "r301" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Value, after forfeiture, of shares granted under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).", "label": "Stock Granted During Period Value Sharebased Compensation", "terseLabel": "Equity-based compensation and related issuance of Class A common stock" } } }, "localname": "StockGrantedDuringPeriodValueSharebasedCompensation", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_StockIssuedDuringPeriodSharesNewIssues": { "auth_ref": [ "r18", "r19", "r243", "r253" ], "lang": { "en-US": { "role": { "documentation": "Number of new stock issued during the period.", "label": "Stock Issued During Period Shares New Issues", "terseLabel": "Issuance of Class A common stock for Newmark RSUs", "verboseLabel": "Stock issued during period, shares, new issues" } } }, "localname": "StockIssuedDuringPeriodSharesNewIssues", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_StockIssuedDuringPeriodSharesOther": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Number of shares of stock issued attributable to transactions classified as other.", "label": "Stock Issued During Period Shares Other", "terseLabel": "Other issuances of Class A common stock" } } }, "localname": "StockIssuedDuringPeriodSharesOther", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures": { "auth_ref": [ "r18", "r19", "r243", "r253" ], "lang": { "en-US": { "role": { "documentation": "Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.", "label": "Stock Issued During Period Shares Restricted Stock Award Net Of Forfeitures", "terseLabel": "Equity-based compensation and related issuance, shares" } } }, "localname": "StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "sharesItemType" }, "us-gaap_StockRepurchasedAndRetiredDuringPeriodShares": { "auth_ref": [ "r18", "r19", "r243", "r253" ], "lang": { "en-US": { "role": { "documentation": "Number of shares that have been repurchased and retired during the period.", "label": "Stock Repurchased And Retired During Period Shares", "terseLabel": "Stock repurchase during period, shares" } } }, "localname": "StockRepurchasedAndRetiredDuringPeriodShares", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_StockRepurchasedDuringPeriodShares": { "auth_ref": [ "r18", "r19", "r243", "r253" ], "lang": { "en-US": { "role": { "documentation": "Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.", "label": "Stock Repurchased During Period Shares", "terseLabel": "Stock repurchased during period", "verboseLabel": "Repurchase of shares" } } }, "localname": "StockRepurchasedDuringPeriodShares", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquityParenthetical" ], "xbrltype": "sharesItemType" }, "us-gaap_StockholdersEquity": { "auth_ref": [ "r19", "r24", "r25", "r164" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10050.0, "parentTag": "us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest", "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", "terseLabel": "Stockholders equity", "totalLabel": "Total stockholders\u2019 equity" } } }, "localname": "StockholdersEquity", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest": { "auth_ref": [ "r338", "r339", "r348" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10040.0, "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity", "weight": 1.0 } }, "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", "totalLabel": "Total equity" } } }, "localname": "StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Stockholders Equity Including Portion Attributable To Noncontrolling Interest [Abstract]", "terseLabel": "Equity:" } } }, "localname": "StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "stringItemType" }, "us-gaap_StockholdersEquityNoteDisclosureTextBlock": { "auth_ref": [ "r259" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.", "label": "Stockholders Equity Note Disclosure [Text Block]", "terseLabel": "Stock Transactions and Unit Redemptions" } } }, "localname": "StockholdersEquityNoteDisclosureTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptions" ], "xbrltype": "textBlockItemType" }, "us-gaap_StockholdersEquityOther": { "auth_ref": [], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy.", "label": "Stockholders Equity Other", "negatedLabel": "Other" } } }, "localname": "StockholdersEquityOther", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "us-gaap_SubleaseIncome": { "auth_ref": [ "r419", "r424" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of sublease income excluding finance and operating lease expense.", "label": "Sublease Income", "terseLabel": "Sublease income" } } }, "localname": "SubleaseIncome", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLeasesAdditionalInformationDetail" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail" ], "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 [Member]" } } }, "localname": "SubsequentEventMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "us-gaap_SubsequentEventTable": { "auth_ref": [ "r436" ], "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.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_SubsequentEventTypeAxis": { "auth_ref": [ "r436" ], "lang": { "en-US": { "role": { "documentation": "Information by event that occurred after the balance sheet date but before financial statements are issued or available to be issued.", "label": "Subsequent Event Type [Axis]", "terseLabel": "Subsequent Event Type" } } }, "localname": "SubsequentEventTypeAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "stringItemType" }, "us-gaap_SubsequentEventTypeDomain": { "auth_ref": [ "r436" ], "lang": { "en-US": { "role": { "documentation": "Event that occurred after the balance sheet date but before financial statements are issued or available to be issued.", "label": "Subsequent Event Type [Domain]", "terseLabel": "Subsequent Event Type" } } }, "localname": "SubsequentEventTypeDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingParentheticalDetail" ], "xbrltype": "domainItemType" }, "us-gaap_SubsequentEventsAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Subsequent Events [Abstract]" } } }, "localname": "SubsequentEventsAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_SubsequentEventsTextBlock": { "auth_ref": [ "r438" ], "lang": { "en-US": { "role": { "documentation": "The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.", "label": "Subsequent Events [Text Block]", "terseLabel": "Subsequent Events" } } }, "localname": "SubsequentEventsTextBlock", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureSubsequentEvents" ], "xbrltype": "textBlockItemType" }, "us-gaap_SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterest": { "auth_ref": [ "r531" ], "lang": { "en-US": { "role": { "documentation": "The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.", "label": "Subsidiary Of Limited Liability Company Or Limited Partnership Ownership Interest", "terseLabel": "Percentage of common shares held by limited partners" } } }, "localname": "SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterest", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail" ], "xbrltype": "percentItemType" }, "us-gaap_SubsidiarySaleOfStockAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by type of sale of the entity's stock.", "label": "Subsidiary Sale Of Stock [Axis]", "terseLabel": "Sale of Stock" } } }, "localname": "SubsidiarySaleOfStockAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_SupplementalCashFlowInformationAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Supplemental Cash Flow Information [Abstract]", "terseLabel": "Supplemental disclosures of cash flow information:" } } }, "localname": "SupplementalCashFlowInformationAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "stringItemType" }, "us-gaap_TaxesPayableCurrent": { "auth_ref": [ "r34" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail": { "order": 10050.0, "parentTag": "us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).", "label": "Taxes Payable Current", "terseLabel": "Corporate and other taxes payable" } } }, "localname": "TaxesPayableCurrent", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureAccountsPayableAccruedExpensesAndOtherLiabilitiesComponentsOfCurrentPortionOfAccountsPayableAccruedExpensesAndOtherLiabilitiesDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_TemporaryEquityAccretionOfDividends": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Value of accretion of temporary equity during the period due to unpaid dividends.", "label": "Temporary Equity Accretion Of Dividends", "negatedLabel": "Distributions of income" } } }, "localname": "TemporaryEquityAccretionOfDividends", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInCarryingAmountOfRedeemablePartnershipInterestDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_TemporaryEquityAccretionToRedemptionValue": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Value of accretion of temporary equity to its redemption value during the period.", "label": "Temporary Equity Accretion To Redemption Value", "negatedLabel": "FPU redemptions" } } }, "localname": "TemporaryEquityAccretionToRedemptionValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInCarryingAmountOfRedeemablePartnershipInterestDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests": { "auth_ref": [ "r49" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10030.0, "parentTag": "us-gaap_LiabilitiesAndStockholdersEquity", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.", "label": "Temporary Equity Carrying Amount Including Portion Attributable To Noncontrolling Interests", "periodEndLabel": "Balance at end of period", "periodStartLabel": "Balance at beginning of period", "terseLabel": "Redeemable partnership interests" } } }, "localname": "TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInCarryingAmountOfRedeemablePartnershipInterestDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_TemporaryEquityNetIncome": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The portion of net income or loss attributable to temporary equity interest.", "label": "Temporary Equity Net Income", "terseLabel": "Income allocation" } } }, "localname": "TemporaryEquityNetIncome", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInCarryingAmountOfRedeemablePartnershipInterestDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_TemporaryEquityOtherChanges": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount of increase (decrease) in temporary equity from changes classified as other.", "label": "Temporary Equity Other Changes", "terseLabel": "Other" } } }, "localname": "TemporaryEquityOtherChanges", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInCarryingAmountOfRedeemablePartnershipInterestDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_TemporaryEquityStockIssuedDuringPeriodValueNewIssues": { "auth_ref": [], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Value of new stock classified as temporary equity issued during the period.", "label": "Temporary Equity Stock Issued During Period Value New Issues", "terseLabel": "Issuance" } } }, "localname": "TemporaryEquityStockIssuedDuringPeriodValueNewIssues", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInCarryingAmountOfRedeemablePartnershipInterestDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_TrademarksAndTradeNamesMember": { "auth_ref": [ "r323" ], "lang": { "en-US": { "role": { "documentation": "Rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style, or rights either acquired through registration of a business name to gain or protect exclusive use thereof.", "label": "Trademarks And Trade Names [Member]", "terseLabel": "Trademark and Trade Names [Member]" } } }, "localname": "TrademarksAndTradeNamesMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureGoodwillAndOtherIntangibleAssetsNetComponentsOfOtherIntangibleAssetsDetail" ], "xbrltype": "domainItemType" }, "us-gaap_TransfersAndServicingAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Transfers And Servicing [Abstract]" } } }, "localname": "TransfersAndServicingAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "xbrltype": "stringItemType" }, "us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain": { "auth_ref": [ "r454" ], "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": "Transfers And Servicing Of Financial Instruments Types Of Financial Instruments [Domain]", "terseLabel": "Financial Instruments" } } }, "localname": "TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesGainsAndLossesOnDerivativeContractsIncludedOnCondensedConsolidatedStatementsOfOperationsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesChangesInLevel3NasdaqForwardsRateLockCommitmentsForwardsAndContingentConsiderationMeasuredAtFairValueOnRecurringBasisDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesFairValueHierarchyOfFinancialAssetsAndLiabilitiesUnderUSGAAPGuidanceDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureFairValueOfFinancialAssetsAndLiabilitiesQuantitativeInformationAboutLevel3FairValueMeasurementsDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail" ], "xbrltype": "domainItemType" }, "us-gaap_TreasuryStockAcquiredAverageCostPerShare": { "auth_ref": [ "r257" ], "lang": { "en-US": { "role": { "documentation": "Total cost of shares repurchased divided by the total number of shares repurchased.", "label": "Treasury Stock Acquired Average Cost Per Share", "terseLabel": "Repurchase, Average Price Paid per Unit", "verboseLabel": "Stock repurchased average price per share" } } }, "localname": "TreasuryStockAcquiredAverageCostPerShare", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsAdditionalInformationDetails", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail" ], "xbrltype": "perShareItemType" }, "us-gaap_TreasuryStockCommonMember": { "auth_ref": [ "r53", "r257" ], "lang": { "en-US": { "role": { "documentation": "Previously issued common shares repurchased by the issuing entity and held in treasury.", "label": "Treasury Stock Common [Member]", "terseLabel": "Treasury Stock [Member]" } } }, "localname": "TreasuryStockCommonMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "domainItemType" }, "us-gaap_TreasuryStockCommonShares": { "auth_ref": [ "r53", "r257" ], "lang": { "en-US": { "role": { "documentation": "Number of previously issued common shares repurchased by the issuing entity and held in treasury.", "label": "Treasury Stock Common Shares", "periodEndLabel": "Balance at Ending of period, Total Number of Shares Repurchased", "periodStartLabel": "Balance at beginning of period, Total Number of Shares Repurchased", "terseLabel": "Treasury stock, shares issued" } } }, "localname": "TreasuryStockCommonShares", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical" ], "xbrltype": "sharesItemType" }, "us-gaap_TreasuryStockCommonValue": { "auth_ref": [ "r53", "r257", "r258" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10120.0, "parentTag": "us-gaap_StockholdersEquity", "weight": -1.0 } }, "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Amount allocated to previously issued common shares repurchased by the issuing entity and held in treasury.", "label": "Treasury Stock Common Value", "negatedLabel": "Treasury stock value" } } }, "localname": "TreasuryStockCommonValue", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_TreasuryStockSharesAcquired": { "auth_ref": [ "r19", "r243", "r253" ], "lang": { "en-US": { "role": { "documentation": "Number of shares that have been repurchased during the period and are being held in treasury.", "label": "Treasury Stock Shares Acquired", "negatedLabel": "Purchase of Newmark treasury stock", "terseLabel": "Repurchase of common stock, shares" } } }, "localname": "TreasuryStockSharesAcquired", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfChangesInSharesOfCommonStockOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureStockTransactionsAndUnitRedemptionsScheduleOfShareRepurchaseActivityDetail" ], "xbrltype": "sharesItemType" }, "us-gaap_TreasuryStockValueAcquiredParValueMethod": { "auth_ref": [ "r243", "r253", "r257" ], "crdr": "debit", "lang": { "en-US": { "role": { "documentation": "Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the par value method.", "label": "Treasury Stock Value Acquired Par Value Method", "negatedLabel": "Repurchase of common stock" } } }, "localname": "TreasuryStockValueAcquiredParValueMethod", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfChangesInEquity" ], "xbrltype": "monetaryItemType" }, "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 [Member]", "terseLabel": "Type of Adoption" } } }, "localname": "TypeOfAdoptionMember", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureRevenuesFromContractsWithCustomersScheduleOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenuesDetail" ], "xbrltype": "domainItemType" }, "us-gaap_TypeOfArrangementAxis": { "auth_ref": [ "r337" ], "lang": { "en-US": { "role": { "documentation": "Information by collaborative arrangement and arrangement other than collaborative applicable to revenue-generating activity or operations.", "label": "Type Of Arrangement [Axis]", "terseLabel": "Collaborative Arrangement and Arrangement Other than Collaborative" } } }, "localname": "TypeOfArrangementAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureCapitalAndLiquidityRequirementsAdditionalInformationDetail" ], "xbrltype": "stringItemType" }, "us-gaap_TypeOfRevenueExtensibleList": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Indicates type of revenue from product and service. Includes, but is not limited to, revenue from contract with customer and other sources.", "label": "Type Of Revenue Extensible List", "terseLabel": "Type of Revenue [Extensible List]" } } }, "localname": "TypeOfRevenueExtensibleList", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "extensibleListItemType" }, "us-gaap_UnrealizedGainLossOnDerivatives": { "auth_ref": [ "r104" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows": { "order": 10470.0, "parentTag": "nmrk_NetIncomeLossAfterAdjustmentsForNoncashAndNonoperatingItems", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.", "label": "Unrealized Gain Loss On Derivatives", "negatedLabel": "Changes in valuation of derivative asset", "negatedTerseLabel": "Valuation of derivative asset" } } }, "localname": "UnrealizedGainLossOnDerivatives", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureDerivativesFairValueOfDerivativeContractsParentheticalDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows" ], "xbrltype": "monetaryItemType" }, "us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued": { "auth_ref": [ "r303" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.", "label": "Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued", "terseLabel": "Accrued interest and penalties related to uncertain tax positions" } } }, "localname": "UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureIncomeTaxesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate": { "auth_ref": [ "r304" ], "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.", "label": "Unrecognized Tax Benefits That Would Impact Effective Tax Rate", "terseLabel": "Unrecognized tax benefits that would affect the effective tax rate" } } }, "localname": "UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureIncomeTaxesAdditionalInformationDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance": { "auth_ref": [ "r460" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail": { "order": 10020.0, "parentTag": "us-gaap_ServicingAsset", "weight": -1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.", "label": "Valuation Allowance For Impairment Of Recognized Servicing Assets Balance", "negatedPeriodEndLabel": "Ending Balance", "negatedPeriodStartLabel": "Beginning Balance" } } }, "localname": "ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ValuationAllowanceForImpairmentOfRecognizedServicingAssetsPeriodIncreaseDecrease": { "auth_ref": [ "r459" ], "lang": { "en-US": { "role": { "documentation": "The net increase (decrease) in the valuation allowance for servicing assets subsequently measured using the amortization method.", "label": "Valuation Allowance For Impairment Of Recognized Servicing Assets Period Increase Decrease", "negatedLabel": "Decrease (increase)" } } }, "localname": "ValuationAllowanceForImpairmentOfRecognizedServicingAssetsPeriodIncreaseDecrease", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "monetaryItemType" }, "us-gaap_ValuationAllowanceForImpairmentOfRecognizedServicingAssetsRollForward": { "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": "Valuation Allowance For Impairment Of Recognized Servicing Assets Roll Forward", "terseLabel": "Valuation Allowance" } } }, "localname": "ValuationAllowanceForImpairmentOfRecognizedServicingAssetsRollForward", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsSummaryOfChangesInCarryingAmountOfMortgageServicingRightsDetail" ], "xbrltype": "stringItemType" }, "us-gaap_VariableRateAxis": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Information by type of variable rate.", "label": "Variable Rate [Axis]", "terseLabel": "Variable Rate" } } }, "localname": "VariableRateAxis", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "stringItemType" }, "us-gaap_VariableRateDomain": { "auth_ref": [], "lang": { "en-US": { "role": { "documentation": "Interest rate that fluctuates over time as a result of an underlying benchmark interest rate or index.", "label": "Variable Rate [Domain]", "terseLabel": "Variable Rate" } } }, "localname": "VariableRateDomain", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureLongTermDebtAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureMortgageServicingRightsNetMsrsAdditionalInformationDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail" ], "xbrltype": "domainItemType" }, "us-gaap_WarehouseAgreementBorrowings": { "auth_ref": [ "r478" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets": { "order": 10160.0, "parentTag": "us-gaap_LiabilitiesCurrent", "weight": 1.0 } }, "crdr": "credit", "lang": { "en-US": { "role": { "documentation": "Carrying value as of the balance sheet date of the outstanding short-term borrowings under a revolving line of credit used by mortgage bankers to finance the origination or purchase of loans.", "label": "Warehouse Agreement Borrowings", "terseLabel": "Warehouse facilities collateralized by U.S. Government Sponsored Enterprises" } } }, "localname": "WarehouseAgreementBorrowings", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureWarehouseFacilitiesCollateralizedByUSGovernmentSponsoredEnterprisesScheduleOfCompanyLinesAvailableAndBorrowingsOutstandingDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedBalanceSheets" ], "xbrltype": "monetaryItemType" }, "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding": { "auth_ref": [ "r127", "r134" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail": { "order": null, "parentTag": null, "root": true, "weight": null } }, "lang": { "en-US": { "role": { "documentation": "The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.", "label": "Weighted Average Number Of Diluted Shares Outstanding", "terseLabel": "Fully diluted weighted-average shares of common stock outstanding", "totalLabel": "Fully diluted weighted-average shares of common stock outstanding" } } }, "localname": "WeightedAverageNumberOfDilutedSharesOutstanding", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "sharesItemType" }, "us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract": { "auth_ref": [], "lang": { "en-US": { "role": { "label": "Weighted Average Number Of Shares Outstanding [Abstract]", "terseLabel": "Weighted-average shares:" } } }, "localname": "WeightedAverageNumberOfSharesOutstandingAbstract", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail" ], "xbrltype": "stringItemType" }, "us-gaap_WeightedAverageNumberOfSharesOutstandingBasic": { "auth_ref": [ "r125", "r134" ], "calculation": { "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail": { "order": 10010.0, "parentTag": "us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding", "weight": 1.0 } }, "lang": { "en-US": { "role": { "documentation": "Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.", "label": "Weighted Average Number Of Shares Outstanding Basic", "terseLabel": "Basic weighted-average shares of common stock outstanding" } } }, "localname": "WeightedAverageNumberOfSharesOutstandingBasic", "nsuri": "http://fasb.org/us-gaap/2019-01-31", "presentation": [ "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfBasicEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/DisclosureEarningsPerShareAndWeightedAverageSharesOutstandingCalculationOfFullyDilutedEarningsPerShareDetail", "http://www.ngkf.com/20190930/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations" ], "xbrltype": "sharesItemType" } }, "unitCount": 7 } }, "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(1))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r100": { "Name": "Accounting Standards Codification", "Paragraph": "25", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(f)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585" }, "r101": { "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" }, "r102": { "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" }, "r103": { "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" }, "r104": { "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" }, "r105": { "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" }, "r106": { "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" }, "r107": { "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" }, "r108": { "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" }, "r109": { "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" }, "r11": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(11))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r110": { "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" }, "r111": { "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" }, "r112": { "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" }, "r113": { "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" }, "r114": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08(k)(1))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r115": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08(k))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r116": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08(m)(1)(iii))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r117": { "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" }, "r118": { "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" }, "r119": { "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" }, "r12": { "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" }, "r120": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08.(k)(1))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r121": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.4-08.(m))", "Topic": "235", "URI": "http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690" }, "r122": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "235", "URI": "http://asc.fasb.org/topic&trid=2122369" }, "r123": { "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" }, "r124": { "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" }, "r125": { "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" }, "r126": { "Name": "Accounting Standards Codification", "Paragraph": "11", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1377-109256" }, "r127": { "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" }, "r128": { "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" }, "r129": { "Name": "Accounting Standards Codification", "Paragraph": "28A", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1500-109256" }, "r13": { "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" }, "r130": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1278-109256" }, "r131": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "260", "URI": "http://asc.fasb.org/extlink&oid=117326831&loc=d3e1311-109256" }, "r132": { "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" }, "r133": { "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" }, "r134": { "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" }, "r135": { "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" }, "r136": { "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" }, "r137": { "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" }, "r138": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "260", "URI": "http://asc.fasb.org/topic&trid=2144383" }, "r139": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "272", "URI": "http://asc.fasb.org/extlink&oid=6828210&loc=d3e70191-108054" }, "r14": { "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" }, "r140": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "272", "URI": "http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055" }, "r141": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "272", "URI": "http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055" }, "r142": { "Name": "Accounting Standards Codification", "Paragraph": "16", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "275", "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6327-108592" }, "r143": { "Name": "Accounting Standards Codification", "Paragraph": "18", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "275", "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592" }, "r144": { "Name": "Accounting Standards Codification", "Paragraph": "20", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "275", "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592" }, "r145": { "Name": "Accounting Standards Codification", "Paragraph": "21", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "275", "URI": "http://asc.fasb.org/extlink&oid=99393423&loc=d3e6442-108592" }, "r146": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "275", "URI": "http://asc.fasb.org/topic&trid=2134479" }, "r147": { "Name": "Accounting Standards Codification", "Paragraph": "22", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599" }, "r148": { "Name": "Accounting Standards Codification", "Paragraph": "22", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599" }, "r149": { "Name": "Accounting Standards Codification", "Paragraph": "22", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(g)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599" }, "r15": { "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" }, "r150": { "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" }, "r151": { "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" }, "r152": { "Name": "Accounting Standards Codification", "Paragraph": "25", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8813-108599" }, "r153": { "Name": "Accounting Standards Codification", "Paragraph": "30", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8906-108599" }, "r154": { "Name": "Accounting Standards Codification", "Paragraph": "31", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8924-108599" }, "r155": { "Name": "Accounting Standards Codification", "Paragraph": "32", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599" }, "r156": { "Name": "Accounting Standards Codification", "Paragraph": "32", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599" }, "r157": { "Name": "Accounting Standards Codification", "Paragraph": "40", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "280", "URI": "http://asc.fasb.org/extlink&oid=115929826&loc=d3e9031-108599" }, "r158": { "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" }, "r159": { "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" }, "r16": { "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" }, "r160": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "310", "URI": "http://asc.fasb.org/extlink&oid=118936363&loc=d3e5066-111524" }, "r161": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "310", "URI": "http://asc.fasb.org/extlink&oid=118936363&loc=d3e5111-111524" }, "r162": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "310", "URI": "http://asc.fasb.org/extlink&oid=118936363&loc=d3e5111-111524" }, "r163": { "Name": "Accounting Standards Codification", "Paragraph": "7A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "310", "URI": "http://asc.fasb.org/extlink&oid=118936363&loc=SL6953401-111524" }, "r164": { "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" }, "r165": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "SubTopic": "10", "Topic": "310", "URI": "http://asc.fasb.org/subtopic&trid=2196772" }, "r166": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "SubTopic": "20", "Topic": "310", "URI": "http://asc.fasb.org/subtopic&trid=2196816" }, "r167": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "320", "URI": "http://asc.fasb.org/extlink&oid=118939692&loc=d3e27405-111563" }, "r168": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "320", "URI": "http://asc.fasb.org/topic&trid=2196928" }, "r169": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "323", "URI": "http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570" }, "r17": { "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" }, "r170": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(1)", "Topic": "323", "URI": "http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571" }, "r171": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(b)", "Topic": "323", "URI": "http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571" }, "r172": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "323", "URI": "http://asc.fasb.org/topic&trid=2196965" }, "r173": { "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" }, "r174": { "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" }, "r175": { "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" }, "r176": { "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" }, "r177": { "Name": "Accounting Standards Codification", "Paragraph": "16", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447" }, "r178": { "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" }, "r179": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447" }, "r18": { "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" }, "r180": { "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" }, "r181": { "Name": "Accounting Standards Codification", "Paragraph": "11", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=118955255&loc=SL82921833-210448" }, "r182": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=118955255&loc=SL82921835-210448" }, "r183": { "Name": "Accounting Standards Codification", "Paragraph": "79", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=118955255&loc=SL82922352-210448" }, "r184": { "Name": "Accounting Standards Codification", "Paragraph": "80", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "326", "URI": "http://asc.fasb.org/extlink&oid=118955255&loc=SL82922355-210448" }, "r185": { "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" }, "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": "4", "Publisher": "FASB", "Section": "05", "SubTopic": "10", "Topic": "340", "URI": "http://asc.fasb.org/extlink&oid=68074540&loc=d3e5865-108316" }, "r19": { "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" }, "r190": { "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" }, "r191": { "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" }, "r192": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266" }, "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": "(b)", "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": "(e)", "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", "Subparagraph": "(g)", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267" }, "r197": { "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" }, "r198": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13854-109267" }, "r199": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=108376223&loc=d3e13854-109267" }, "r2": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(d)", "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(3)(a)(2))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r200": { "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" }, "r201": { "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" }, "r202": { "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" }, "r203": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(a)(3)", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275" }, "r204": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(b)", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275" }, "r205": { "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" }, "r206": { "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" }, "r207": { "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" }, "r208": { "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" }, "r209": { "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" }, "r21": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02(3)(a)(3))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r210": { "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" }, "r211": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(b)", "Topic": "350", "URI": "http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275" }, "r212": { "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" }, "r213": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "350", "URI": "http://asc.fasb.org/topic&trid=2144416" }, "r214": { "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" }, "r215": { "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" }, "r216": { "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" }, "r217": { "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" }, "r218": { "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" }, "r219": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "360", "URI": "http://asc.fasb.org/topic&trid=2155823" }, "r22": { "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" }, "r220": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "440", "URI": "http://asc.fasb.org/topic&trid=2144648" }, "r221": { "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" }, "r222": { "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" }, "r223": { "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" }, "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", "Topic": "450", "URI": "http://asc.fasb.org/extlink&oid=118942415&loc=d3e14557-108349" }, "r228": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "450", "URI": "http://asc.fasb.org/topic&trid=2127136" }, "r229": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "25", "SubTopic": "10", "Topic": "460", "URI": "http://asc.fasb.org/extlink&oid=118943535&loc=d3e11019-110243" }, "r23": { "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" }, "r230": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "25", "SubTopic": "10", "Topic": "460", "URI": "http://asc.fasb.org/extlink&oid=118943535&loc=d3e11049-110243" }, "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": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "460", "URI": "http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248" }, "r234": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)(1)", "Topic": "460", "URI": "http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248" }, "r235": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "460", "URI": "http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248" }, "r236": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "460", "URI": "http://asc.fasb.org/extlink&oid=118943654&loc=d3e12265-110248" }, "r237": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "460", "URI": "http://asc.fasb.org/topic&trid=2155896" }, "r238": { "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" }, "r239": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "470", "URI": "http://asc.fasb.org/topic&trid=2208564" }, "r24": { "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" }, "r240": { "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" }, "r241": { "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" }, "r242": { "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" }, "r243": { "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" }, "r244": { "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" }, "r245": { "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" }, "r246": { "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" }, "r247": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644" }, "r248": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644" }, "r249": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644" }, "r25": { "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" }, "r250": { "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" }, "r251": { "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" }, "r252": { "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" }, "r253": { "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" }, "r254": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770" }, "r255": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SAB TOPIC 4.F)", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770" }, "r256": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SAB Topic 4.F)", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770" }, "r257": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "30", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655" }, "r258": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "505", "URI": "http://asc.fasb.org/extlink&oid=6405834&loc=d3e23315-112656" }, "r259": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "505", "URI": "http://asc.fasb.org/topic&trid=2208762" }, "r26": { "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" }, "r260": { "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" }, "r261": { "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" }, "r262": { "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" }, "r263": { "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" }, "r264": { "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" }, "r265": { "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" }, "r266": { "Name": "Accounting Standards Codification", "Paragraph": "91", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=118944142&loc=SL49130690-203046-203046" }, "r267": { "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" }, "r268": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "65", "SubTopic": "10", "Subparagraph": "(i)(1)", "Topic": "606", "URI": "http://asc.fasb.org/extlink&oid=113356391&loc=SL49131195-203048" }, "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 210.5-02.1)", "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": "30", "SubTopic": "10", "Topic": "710", "URI": "http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363" }, "r272": { "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" }, "r273": { "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" }, "r274": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(n)", "Topic": "715", "URI": "http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920" }, "r275": { "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" }, "r276": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "30", "SubTopic": "10", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116855757&loc=d3e3913-113898" }, "r277": { "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" }, "r278": { "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" }, "r279": { "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" }, "r28": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.12)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r280": { "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" }, "r281": { "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" }, "r282": { "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" }, "r283": { "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" }, "r284": { "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" }, "r285": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(1)(ii)", "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": "(c)(1)(iv)(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)(1)(iv)(2)", "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)(iv)(3)", "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)(2)", "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)", "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)(2)(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)(2)(iii)(1)", "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)(2)(iii)(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)(2)(iii)(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": "(d)", "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": "(e)", "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": "(e)(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": "(h)(1)(i)", "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": "(i)", "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", "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": "(f)", "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 210.5-02.14)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r300": { "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" }, "r301": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "35", "SubTopic": "30", "Topic": "718", "URI": "http://asc.fasb.org/extlink&oid=116859318&loc=d3e15009-113911" }, "r302": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "718", "URI": "http://asc.fasb.org/topic&trid=2228938" }, "r303": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319" }, "r304": { "Name": "Accounting Standards Codification", "Paragraph": "15A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319" }, "r305": { "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" }, "r306": { "Name": "Accounting Standards Codification", "Paragraph": "9", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "740", "URI": "http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319" }, "r307": { "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" }, "r308": { "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" }, "r309": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "740", "URI": "http://asc.fasb.org/topic&trid=2144680" }, "r31": { "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" }, "r310": { "Name": "Accounting Standards Codification", "Paragraph": "16", "Publisher": "FASB", "Section": "25", "SubTopic": "10", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116868678&loc=d3e961-128460" }, "r311": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "25", "SubTopic": "10", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116868678&loc=d3e845-128460" }, "r312": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "25", "SubTopic": "10", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116868678&loc=d3e848-128460" }, "r313": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463" }, "r314": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463" }, "r315": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(h)(1)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463" }, "r316": { "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" }, "r317": { "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" }, "r318": { "Name": "Accounting Standards Codification", "Paragraph": "37", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116868840&loc=d3e2207-128464" }, "r319": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472" }, "r32": { "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" }, "r320": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(e)(1)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472" }, "r321": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472" }, "r322": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=77890550&loc=d3e5227-128473" }, "r323": { "Name": "Accounting Standards Codification", "Paragraph": "14", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=77890550&loc=d3e5263-128473" }, "r324": { "Name": "Accounting Standards Codification", "Paragraph": "14", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Subparagraph": "(e)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=77890550&loc=d3e5263-128473" }, "r325": { "Name": "Accounting Standards Codification", "Paragraph": "20", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=77890550&loc=d3e5333-128473" }, "r326": { "Name": "Accounting Standards Codification", "Paragraph": "31", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=77890550&loc=d3e5419-128473" }, "r327": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "25", "SubTopic": "30", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476" }, "r328": { "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" }, "r329": { "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" }, "r33": { "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" }, "r330": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "35", "SubTopic": "30", "Subparagraph": "b", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478" }, "r331": { "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" }, "r332": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(b)(4)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479" }, "r333": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(c)(3)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479" }, "r334": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(d)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479" }, "r335": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(a)(1)", "Topic": "805", "URI": "http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479" }, "r336": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "805", "URI": "http://asc.fasb.org/topic&trid=2303972" }, "r337": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "808", "URI": "http://asc.fasb.org/extlink&oid=6931272&loc=SL5834143-161434" }, "r338": { "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" }, "r339": { "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" }, "r34": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.19,20)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r340": { "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" }, "r341": { "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" }, "r342": { "Name": "Accounting Standards Codification", "Paragraph": "21", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4613674-111683" }, "r343": { "Name": "Accounting Standards Codification", "Paragraph": "23", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=108774443&loc=SL4569655-111683" }, "r344": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(1)", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684" }, "r345": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)(2)", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684" }, "r346": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(1)", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684" }, "r347": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(2)", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684" }, "r348": { "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" }, "r349": { "Name": "Accounting Standards Codification", "Paragraph": "4J", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=116874947&loc=SL4591551-111686" }, "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": "4K", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=116874947&loc=SL4591552-111686" }, "r351": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.3A-04)", "Topic": "810", "URI": "http://asc.fasb.org/extlink&oid=116822174&loc=d3e355119-122828" }, "r352": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "810", "URI": "http://asc.fasb.org/topic&trid=2197479" }, "r353": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959" }, "r354": { "Name": "Accounting Standards Codification", "Paragraph": "1B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959" }, "r355": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=d3e41620-113959" }, "r356": { "Name": "Accounting Standards Codification", "Paragraph": "4A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959" }, "r357": { "Name": "Accounting Standards Codification", "Paragraph": "4A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959" }, "r358": { "Name": "Accounting Standards Codification", "Paragraph": "4A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)(1)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959" }, "r359": { "Name": "Accounting Standards Codification", "Paragraph": "4B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(1)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959" }, "r36": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.2)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r360": { "Name": "Accounting Standards Codification", "Paragraph": "4B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(2)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959" }, "r361": { "Name": "Accounting Standards Codification", "Paragraph": "4B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959" }, "r362": { "Name": "Accounting Standards Codification", "Paragraph": "4B", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959" }, "r363": { "Name": "Accounting Standards Codification", "Paragraph": "4C", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959" }, "r364": { "Name": "Accounting Standards Codification", "Paragraph": "4D", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959" }, "r365": { "Name": "Accounting Standards Codification", "Paragraph": "4D", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959" }, "r366": { "Name": "Accounting Standards Codification", "Paragraph": "4E", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109980867&loc=SL5624181-113959" }, "r367": { "Name": "Accounting Standards Codification", "Paragraph": "182", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=116861445&loc=SL5629052-113961" }, "r368": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "25", "Topic": "815", "URI": "http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986" }, "r369": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "815", "URI": "http://asc.fasb.org/topic&trid=2229140" }, "r37": { "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" }, "r370": { "Name": "Accounting Standards Codification", "Paragraph": "54B", "Publisher": "FASB", "Section": "35", "SubTopic": "10", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117332851&loc=SL7495116-110257" }, "r371": { "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" }, "r372": { "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" }, "r373": { "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" }, "r374": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(bbb)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r375": { "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" }, "r376": { "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" }, "r377": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r378": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(1)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r379": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(2)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r38": { "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" }, "r380": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)(3)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r381": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r382": { "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" }, "r383": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258" }, "r384": { "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" }, "r385": { "Name": "Accounting Standards Codification", "Paragraph": "6A", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "820", "URI": "http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258" }, "r386": { "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" }, "r387": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=116690757&loc=d3e13220-108610" }, "r388": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611" }, "r389": { "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" }, "r39": { "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" }, "r390": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=118260190&loc=d3e13476-108611" }, "r391": { "Name": "Accounting Standards Codification", "Paragraph": "20", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611" }, "r392": { "Name": "Accounting Standards Codification", "Paragraph": "21", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(a)", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611" }, "r393": { "Name": "Accounting Standards Codification", "Paragraph": "21", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611" }, "r394": { "Name": "Accounting Standards Codification", "Paragraph": "21", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611" }, "r395": { "Name": "Accounting Standards Codification", "Paragraph": "28", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612" }, "r396": { "Name": "Accounting Standards Codification", "Paragraph": "30", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612" }, "r397": { "Name": "Accounting Standards Codification", "Paragraph": "31", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=75031198&loc=d3e14210-108612" }, "r398": { "Name": "Accounting Standards Codification", "Paragraph": "32", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "825", "URI": "http://asc.fasb.org/extlink&oid=75031198&loc=d3e14217-108612" }, "r399": { "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" }, "r4": { "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" }, "r40": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.22(a)(2))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r400": { "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" }, "r401": { "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" }, "r402": { "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" }, "r403": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "45", "SubTopic": "30", "Topic": "835", "URI": "http://asc.fasb.org/extlink&oid=114775744&loc=d3e28567-108399" }, "r404": { "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" }, "r405": { "Name": "Accounting Standards Codification", "Paragraph": "40", "Publisher": "FASB", "Section": "55", "SubTopic": "10", "Subparagraph": "(Note 3)", "Topic": "840", "URI": "http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697" }, "r406": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "25", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "840", "URI": "http://asc.fasb.org/extlink&oid=77902458&loc=d3e39927-112707" }, "r407": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(a)", "Topic": "840", "URI": "http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717" }, "r408": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "840", "URI": "http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717" }, "r409": { "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" }, "r41": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.22(a)(3))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r410": { "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" }, "r411": { "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" }, "r412": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888419&loc=SL77918631-209977" }, "r413": { "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" }, "r414": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918666-209980" }, "r415": { "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" }, "r416": { "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" }, "r417": { "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" }, "r418": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980" }, "r419": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(e)", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980" }, "r42": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.22(a))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r420": { "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" }, "r421": { "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" }, "r422": { "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" }, "r423": { "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" }, "r424": { "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" }, "r425": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "SubTopic": "20", "Topic": "842", "URI": "http://asc.fasb.org/subtopic&trid=77888251" }, "r426": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "45", "SubTopic": "30", "Topic": "842", "URI": "http://asc.fasb.org/extlink&oid=77888421&loc=SL77919311-209978" }, "r427": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864" }, "r428": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Subparagraph": "(d)", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864" }, "r429": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864" }, "r43": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.22(b))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r430": { "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" }, "r431": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864" }, "r432": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864" }, "r433": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39678-107864" }, "r434": { "Name": "Accounting Standards Codification", "Paragraph": "6", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "850", "URI": "http://asc.fasb.org/extlink&oid=6457730&loc=d3e39691-107864" }, "r435": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "850", "URI": "http://asc.fasb.org/topic&trid=2122745" }, "r436": { "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" }, "r437": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "10", "Topic": "855", "URI": "http://asc.fasb.org/extlink&oid=6842918&loc=SL6314020-165662" }, "r438": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "855", "URI": "http://asc.fasb.org/topic&trid=2122774" }, "r439": { "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" }, "r44": { "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" }, "r440": { "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" }, "r441": { "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" }, "r442": { "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" }, "r443": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Subparagraph": "(b)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729" }, "r444": { "Name": "Accounting Standards Codification", "Paragraph": "1A", "Publisher": "FASB", "Section": "50", "SubTopic": "30", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729" }, "r445": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "25", "SubTopic": "50", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=7524895&loc=d3e120260-111741" }, "r446": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "50", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745" }, "r447": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "50", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745" }, "r448": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(b)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746" }, "r449": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(c)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746" }, "r45": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.23)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r450": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(d)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746" }, "r451": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(a)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746" }, "r452": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(a)(1)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746" }, "r453": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(a)(2)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746" }, "r454": { "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" }, "r455": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(a)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746" }, "r456": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(a)(1)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746" }, "r457": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(a)(2)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746" }, "r458": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(a)(4)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746" }, "r459": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(e)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746" }, "r46": { "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" }, "r460": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "50", "SubTopic": "50", "Subparagraph": "(e)(1)", "Topic": "860", "URI": "http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746" }, "r461": { "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" }, "r462": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(a)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61929-109447" }, "r463": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(b)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61929-109447" }, "r464": { "Name": "Accounting Standards Codification", "Paragraph": "20", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(a)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e62059-109447" }, "r465": { "Name": "Accounting Standards Codification", "Paragraph": "20", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(b)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e62059-109447" }, "r466": { "Name": "Accounting Standards Codification", "Paragraph": "28", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(a)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e62395-109447" }, "r467": { "Name": "Accounting Standards Codification", "Paragraph": "28", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(b)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e62395-109447" }, "r468": { "Name": "Accounting Standards Codification", "Paragraph": "33", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(a)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e62479-109447" }, "r469": { "Name": "Accounting Standards Codification", "Paragraph": "33", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(b)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e62479-109447" }, "r47": { "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" }, "r470": { "Name": "Accounting Standards Codification", "Paragraph": "35A", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(a)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447" }, "r471": { "Name": "Accounting Standards Codification", "Paragraph": "35A", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(b)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447" }, "r472": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(c)(1)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61872-109447" }, "r473": { "Name": "Accounting Standards Codification", "Paragraph": "8", "Publisher": "FASB", "Section": "50", "SubTopic": "235", "Subparagraph": "(c)(2)", "Topic": "932", "URI": "http://asc.fasb.org/extlink&oid=68064819&loc=d3e61872-109447" }, "r474": { "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" }, "r475": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "SubTopic": "320", "Topic": "940", "URI": "http://asc.fasb.org/subtopic&trid=2176304" }, "r476": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "Topic": "940", "URI": "http://asc.fasb.org/topic&trid=2176223" }, "r477": { "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" }, "r478": { "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" }, "r479": { "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" }, "r48": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.26(c))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r480": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03(22))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r481": { "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" }, "r482": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03.10)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r483": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.9-03.15)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878" }, "r484": { "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" }, "r485": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.9-04(13)(f))", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r486": { "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" }, "r487": { "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" }, "r488": { "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" }, "r489": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.9-04.1)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r49": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.27(b))", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r490": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.9-04.10)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r491": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.9-04.8)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260" }, "r492": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "SubTopic": "320", "Topic": "942", "URI": "http://asc.fasb.org/subtopic&trid=2209399" }, "r493": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "405", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817" }, "r494": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "470", "Subparagraph": "(c)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823" }, "r495": { "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" }, "r496": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "505", "Subparagraph": "(c)(1)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826" }, "r497": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "505", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826" }, "r498": { "Name": "Accounting Standards Codification", "Paragraph": "1B", "Publisher": "FASB", "Section": "50", "SubTopic": "505", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826" }, "r499": { "Name": "Accounting Standards Codification", "Paragraph": "1G", "Publisher": "FASB", "Section": "50", "SubTopic": "505", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=117337116&loc=SL5958577-112826" }, "r5": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(g)(4)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765" }, "r50": { "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" }, "r500": { "Name": "Accounting Standards Codification", "Paragraph": "1H", "Publisher": "FASB", "Section": "50", "SubTopic": "505", "Subparagraph": "(c)(2)", "Topic": "942", "URI": "http://asc.fasb.org/extlink&oid=117337116&loc=d3e65071-112826" }, "r501": { "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" }, "r502": { "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" }, "r503": { "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" }, "r504": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(24))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r505": { "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" }, "r506": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03(a)(3))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r507": { "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" }, "r508": { "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" }, "r509": { "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" }, "r51": { "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" }, "r510": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.7-03.15)", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910" }, "r511": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.7-04(10))", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263" }, "r512": { "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" }, "r513": { "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" }, "r514": { "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" }, "r515": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "45", "SubTopic": "310", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=118959141&loc=d3e21286-158488" }, "r516": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "310", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=118959141&loc=d3e21310-158488" }, "r517": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "310", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=117337389&loc=d3e21493-158490" }, "r518": { "Name": "Accounting Standards Codification", "Paragraph": "4H", "Publisher": "FASB", "Section": "50", "SubTopic": "40", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=116884468&loc=SL65671331-158438" }, "r519": { "Name": "Accounting Standards Codification", "Paragraph": "13H", "Publisher": "FASB", "Section": "55", "SubTopic": "40", "Subparagraph": "(a)", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=117419784&loc=SL117783719-158441" }, "r52": { "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" }, "r520": { "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" }, "r521": { "Name": "Accounting Standards Codification", "Paragraph": "1B", "Publisher": "FASB", "Section": "50", "SubTopic": "825", "Topic": "944", "URI": "http://asc.fasb.org/extlink&oid=99380617&loc=SL75241803-196195" }, "r522": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "50", "SubTopic": "205", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=25866437&loc=d3e10246-115837" }, "r523": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.6-04(16))", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996" }, "r524": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.6-04.16(a))", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996" }, "r525": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "210", "Subparagraph": "(SX 210.6-04.16)", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996" }, "r526": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "220", "Subparagraph": "(SX 210.6-07.1(c))", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=116637345&loc=SL114874292-224272" }, "r527": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "320", "Subparagraph": "(SX 210.12-12(2)(i))", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=50485924&loc=d3e611133-123010" }, "r528": { "Name": "Accounting Standards Codification", "Paragraph": "4", "Publisher": "FASB", "Section": "S99", "SubTopic": "320", "Subparagraph": "(SX 210.12-12C(1)(a))", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=50485924&loc=d3e611225-123010" }, "r529": { "Name": "Accounting Standards Codification", "Paragraph": "5", "Publisher": "FASB", "Section": "S99", "SubTopic": "320", "Subparagraph": "(SX 210.12-13(1))", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=50485924&loc=d3e611282-123010" }, "r53": { "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" }, "r530": { "Name": "Accounting Standards Codification", "Paragraph": "7", "Publisher": "FASB", "Section": "S99", "SubTopic": "320", "Subparagraph": "(SX 210.12-15(Column A))", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=50485924&loc=d3e611379-123010" }, "r531": { "Name": "Accounting Standards Codification", "Paragraph": "9", "Publisher": "FASB", "Section": "S99", "SubTopic": "320", "Topic": "946", "URI": "http://asc.fasb.org/extlink&oid=50485924&loc=d3e611443-123010" }, "r532": { "Name": "Accounting Standards Codification", "Publisher": "FASB", "SubTopic": "320", "Topic": "946", "URI": "http://asc.fasb.org/subtopic&trid=2324412" }, "r533": { "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" }, "r534": { "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" }, "r535": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "360", "Subparagraph": "(SX 210.12-28(Footnote 4))", "Topic": "970", "URI": "http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024" }, "r536": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(b)(1)", "Topic": "985", "URI": "http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756" }, "r537": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Topic": "985", "URI": "http://asc.fasb.org/extlink&oid=6501960&loc=d3e128487-111756" }, "r538": { "Name": "Exchange Act", "Number": "240", "Publisher": "SEC", "Section": "12", "Subsection": "b" }, "r539": { "Name": "Exchange Act", "Number": "240", "Publisher": "SEC", "Section": "12", "Subsection": "d1-1" }, "r54": { "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" }, "r540": { "Name": "Form 10-Q", "Number": "240", "Publisher": "SEC", "Section": "13", "Subsection": "a-13" }, "r541": { "Name": "Forms 10-K, 10-Q, 20-F", "Number": "240", "Publisher": "SEC", "Section": "13", "Subsection": "a-1-" }, "r542": { "Name": "Regulation 12B", "Number": "240", "Publisher": "SEC", "Section": "12", "Subsection": "b-2" }, "r543": { "Name": "Regulation S-T", "Number": "232", "Publisher": "SEC", "Section": "405" }, "r55": { "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" }, "r56": { "Name": "Accounting Standards Codification", "Paragraph": "1", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-02.8,17)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682" }, "r57": { "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" }, "r58": { "Name": "Accounting Standards Codification", "Paragraph": "11", "Publisher": "FASB", "Section": "45", "SubTopic": "20", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=49176635&loc=d3e9760-107771" }, "r59": { "Name": "Accounting Standards Codification", "Paragraph": "3", "Publisher": "FASB", "Section": "50", "SubTopic": "20", "Subparagraph": "(c)", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312" }, "r6": { "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" }, "r60": { "Name": "Accounting Standards Codification", "Paragraph": "10", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313" }, "r61": { "Name": "Accounting Standards Codification", "Paragraph": "16", "Publisher": "FASB", "Section": "55", "SubTopic": "20", "Topic": "210", "URI": "http://asc.fasb.org/extlink&oid=99393222&loc=SL20226024-175313" }, "r62": { "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" }, "r63": { "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" }, "r64": { "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" }, "r65": { "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" }, "r66": { "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" }, "r67": { "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" }, "r68": { "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" }, "r69": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(12))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r7": { "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" }, "r70": { "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" }, "r71": { "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" }, "r72": { "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" }, "r73": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03(7)(c))", "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(8))", "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(b)(2))", "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)", "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 210.5-03.1(e))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r78": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03.19)", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r79": { "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" }, "r8": { "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" }, "r80": { "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" }, "r81": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "S99", "SubTopic": "10", "Subparagraph": "(SX 210.5-03.7(c),9(a))", "Topic": "220", "URI": "http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227" }, "r82": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585" }, "r83": { "Name": "Accounting Standards Codification", "Paragraph": "12", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585" }, "r84": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(b)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585" }, "r85": { "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" }, "r86": { "Name": "Accounting Standards Codification", "Paragraph": "13", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585" }, "r87": { "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" }, "r88": { "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" }, "r89": { "Name": "Accounting Standards Codification", "Paragraph": "14", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585" }, "r9": { "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" }, "r90": { "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" }, "r91": { "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" }, "r92": { "Name": "Accounting Standards Codification", "Paragraph": "15", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585" }, "r93": { "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" }, "r94": { "Name": "Accounting Standards Codification", "Paragraph": "2", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3000-108585" }, "r95": { "Name": "Accounting Standards Codification", "Paragraph": "21", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3461-108585" }, "r96": { "Name": "Accounting Standards Codification", "Paragraph": "21D", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=SL94080555-108585" }, "r97": { "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" }, "r98": { "Name": "Accounting Standards Codification", "Paragraph": "25", "Publisher": "FASB", "Section": "45", "SubTopic": "10", "Subparagraph": "(c)", "Topic": "230", "URI": "http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585" }, "r99": { "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" } }, "version": "2.1" }