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4ghl_UnfundedInvestmentCommitmentsghl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17truefalsefalse29000002900000falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20truefalsefalse100000100000falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryUnfunded Investment CommitmentsNo definition available.false2Unfunded commitments9false 4us-gaap_InvestmentOwnedBalanceSharesus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23truefalsefalse33590163359016falsefalsefalse24falsefalsefalse00falsefalsefalse25truefalsefalse33590163359016falsefalsefalse26falsefalsefalse00falsefalsefalse27truefalsefalse50840165084016falsefalsefalsexbrli:sharesItemTypesharesBalance held at close of period in number of shares.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 12C -Paragraph Column B -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 12 -Paragraph Column B -Article 12 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 14 -Paragraph Column B -Article 12 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14.Column B) -URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611322-123010 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12.Column B) -URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611133-123010 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-12C.Column B) -URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611225-123010 false1Investment in Iridium (shares)10false 4us-gaap_SharePriceus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23truefalsefalse7.767.76USD$falsetruefalse24falsefalsefalse00falsefalsefalse25truefalsefalse7.767.76USD$falsetruefalse26falsefalsefalse00falsefalsefalse27truefalsefalse6.726.72USD$falsetruefalsenum:perShareItemTypedecimalPrice of a single share of a number of saleable stocks of a company.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false3Share price (usd per share)11false 4ghl_PercentageOfOwnershipInterestsghl_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalse11falsetruefalse00falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalse14falsetruefalse00falsefalsefalse15falsetruefalse00falsefalsefalse16falsetruefalse00falsefalsefalse17falsetruefalse00falsefalsefalse18falsetruefalse00falsefalsefalse19falsetruefalse00falsefalsefalse20falsetruefalse00falsefalsefalse21falsetruefalse00falsefalsefalse22falsetruefalse00falsefalsefalse23truetruefalse0.040.04falsefalsefalse24falsetruefalse00falsefalsefalse25truetruefalse0.040.04falsefalsefalse26falsetruefalse00falsefalsefalse27truetruefalse0.070.07falsefalsefalsenum:percentItemTypepureThe percentage of ownership interestests which is fully diluted.No definition available.false0The percentage of ownership interestests which is fully diluted (percent)12false 4us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVenturesus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1299700012997000USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse1677200016772000USD$falsetruefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8truefalsefalse75160007516000USD$falsetruefalse9truefalsefalse1117300011173000USD$falsetruefalse10truefalsefalse15870001587000USD$falsetruefalse11truefalsefalse22470002247000USD$falsetruefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17truefalsefalse20250002025000USD$falsetruefalse18truefalsefalse13670001367000USD$falsetruefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 false2Investments in merchant banking funds13false 4ghl_FiniteLivedPartnershipTerminationDateghl_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse002015falsefalsefalse21falsefalsefalse00falsefalsefalse22falsefalsefalse00falsefalsefalse23falsefalsefalse00falsefalsefalse24falsefalsefalse00falsefalsefalse25falsefalsefalse00falsefalsefalse26falsefalsefalse00falsefalsefalse27falsefalsefalse00falsefalsefalsexbrli:gYearItemTypepositiveintegerFinite Lived Partnership, Termination DateNo definition available.false0Fund commitments, expirationfalseInvestments - Additional Information (Detail) (USD $)NoRoundingNoRoundingNoRoundingUnKnowntruefalsefalseSheethttp://www.greenhill.com/role/InvestmentsAdditionalInformationDetail2713