v2.4.1.9
Financial Assets and Liabilities at Fair Value (Detail) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Blackstone's Treasury Cash Management Strategies $ 1,631,696bx_InvestmentsInTreasuryCashManagementStrategies $ 1,666,061bx_InvestmentsInTreasuryCashManagementStrategies
Money Market Funds 260,002bx_MoneyMarketFundsFairValue 198,278bx_MoneyMarketFundsFairValue
Net Investment Hedges - Foreign Currency Contracts   523us-gaap_NetInvestmentHedgeDerivativeAssetsAtFairValue
Freestanding Derivatives, Assets 9,557us-gaap_DerivativeFairValueOfDerivativeAsset 15,009us-gaap_DerivativeFairValueOfDerivativeAsset
Investments of Consolidated Funds 11,123,132bx_InvestmentsOfConsolidatedFunds 11,375,407bx_InvestmentsOfConsolidatedFunds
Freestanding Derivatives, Liabilities 48,604us-gaap_DerivativeFairValueOfDerivativeLiability 30,528us-gaap_DerivativeFairValueOfDerivativeLiability
Other Investments 154,069us-gaap_OtherInvestments 146,251us-gaap_OtherInvestments
Total Financial Assets 13,211,996bx_TotalFinancialAssetsFairValue 13,430,207bx_TotalFinancialAssetsFairValue
Securities Sold, Not Yet Purchased 162,111us-gaap_SecurityOwnedAndSoldNotYetPurchasedFairValueSecuritySoldNotYetPurchased 85,878us-gaap_SecurityOwnedAndSoldNotYetPurchasedFairValueSecuritySoldNotYetPurchased
Total Financial Liabilities 7,144,462us-gaap_FinancialLiabilitiesFairValueDisclosure 6,913,510us-gaap_FinancialLiabilitiesFairValueDisclosure
Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 9,557us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
14,486us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
Freestanding Derivatives, Liabilities 48,196us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
30,528us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
Corporate Loans    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Corporate Loans 5,902,169bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
6,279,592bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
Loans And Receivables    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Loans and Receivables 40,691us-gaap_LoansReceivableFairValueDisclosure
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= bx_LoansAndReceivablesMember
40,397us-gaap_LoansReceivableFairValueDisclosure
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= bx_LoansAndReceivablesMember
Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment Funds 1,170,378bx_InvestmentFundsFairValue
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 1,103,210bx_InvestmentFundsFairValue
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Equity Securities 339,736bx_EquitySecuritiesFairValue
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 352,360bx_EquitySecuritiesFairValue
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Partnership and LLC Interests 1,746,016bx_PartnershipAndLlcInterestsFairValue
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 1,683,562bx_PartnershipAndLlcInterestsFairValue
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Debt Instruments 1,559,599us-gaap_DebtInstrumentFairValue
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 1,608,284us-gaap_DebtInstrumentFairValue
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Investments of Consolidated Funds 11,123,132bx_InvestmentsOfConsolidatedFunds
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 11,375,407bx_InvestmentsOfConsolidatedFunds
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Investments Of Consolidated Blackstone Funds | Corporate Loans    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Corporate Loans 5,902,169bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
[1] 6,279,592bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
[1]
Blackstone's Treasury Cash Management Strategies    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment Funds 276,611bx_InvestmentFundsFairValue
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
307,111bx_InvestmentFundsFairValue
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Equity Securities 69,849bx_EquitySecuritiesFairValue
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
71,746bx_EquitySecuritiesFairValue
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Debt Instruments 1,223,523us-gaap_DebtInstrumentFairValue
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
1,226,195us-gaap_DebtInstrumentFairValue
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Other 61,713bx_OtherAssetsAtFairValue
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
61,009bx_OtherAssetsAtFairValue
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Total Blackstone's Treasury Cash Management Strategies 1,631,696bx_InvestmentsInTreasuryCashManagementStrategies
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
1,666,061bx_InvestmentsInTreasuryCashManagementStrategies
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Corporate Bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Corporate Bonds 322,696bx_AssetsOfConsolidatedCloVehiclesCorporateBondsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateBondSecuritiesMember
292,690bx_AssetsOfConsolidatedCloVehiclesCorporateBondsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateBondSecuritiesMember
Corporate Bonds | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Corporate Bonds 322,696bx_AssetsOfConsolidatedCloVehiclesCorporateBondsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateBondSecuritiesMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 292,690bx_AssetsOfConsolidatedCloVehiclesCorporateBondsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateBondSecuritiesMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Foreign Currency Contracts    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Net Investment Hedges - Foreign Currency Contracts   523us-gaap_NetInvestmentHedgeDerivativeAssetsAtFairValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
Net Investment Hedges - Foreign Currency Contracts 408us-gaap_NetInvestmentHedgeDerivativeLiabilitiesAtFairValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
[1]  
Foreign Currency Contracts | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 1,647us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
2,798us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
Freestanding Derivatives, Liabilities 2,593us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
681us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
Foreign Currency Contracts | Investments Of Consolidated Blackstone Funds | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 5,118us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 8,915us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Interest Rate Contracts | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 451us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
407us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
Freestanding Derivatives, Liabilities 7,458us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
4,590us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
Interest Rate Contracts | Investments Of Consolidated Blackstone Funds | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 2,033us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 2,281us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Credit Default Swaps | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 308us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
85us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
Freestanding Derivatives, Liabilities 1,464us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
868us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
Other    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other 75,387bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
44,513bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
Other | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other 75,387bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
[1] 44,513bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
[1]
Liabilities of Consolidated CLO Vehicles | Foreign Currency Contracts | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Liabilities 36,138us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
[1] 21,875us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
[1]
Liabilities of Consolidated CLO Vehicles | Credit Default Swaps | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Liabilities 543us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
[1] 2,514us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
[1]
Liabilities of Consolidated CLO Vehicles | Senior Secured Notes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair value of Notes 6,587,954us-gaap_NotesPayableFairValueDisclosure
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_SeniorNotesMember
[1] 6,448,352us-gaap_NotesPayableFairValueDisclosure
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_SeniorNotesMember
[1]
Liabilities of Consolidated CLO Vehicles | Subordinated Notes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair value of Notes 345,793us-gaap_NotesPayableFairValueDisclosure
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_SeniorSubordinatedNotesMember
[1] 348,752us-gaap_NotesPayableFairValueDisclosure
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_SeniorSubordinatedNotesMember
[1]
Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money Market Funds 260,002bx_MoneyMarketFundsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
198,278bx_MoneyMarketFundsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
Other Investments 35,379us-gaap_OtherInvestments
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
31,731us-gaap_OtherInvestments
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
Total Financial Assets 707,752bx_TotalFinancialAssetsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
668,076bx_TotalFinancialAssetsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
Total Financial Liabilities 2,813us-gaap_FinancialLiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
1,357us-gaap_FinancialLiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
Level 1 | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity Securities 65,706bx_EquitySecuritiesFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 58,934bx_EquitySecuritiesFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Investments of Consolidated Funds 65,720bx_InvestmentsOfConsolidatedFunds
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 58,947bx_InvestmentsOfConsolidatedFunds
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Level 1 | Blackstone's Treasury Cash Management Strategies    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment Funds 276,611bx_InvestmentFundsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
307,111bx_InvestmentFundsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Equity Securities 69,849bx_EquitySecuritiesFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
71,746bx_EquitySecuritiesFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Total Blackstone's Treasury Cash Management Strategies 346,460bx_InvestmentsInTreasuryCashManagementStrategies
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
378,857bx_InvestmentsInTreasuryCashManagementStrategies
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Level 1 | Interest Rate Contracts | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 191us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
263us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
Freestanding Derivatives, Liabilities 2,813us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
1,357us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
Level 1 | Other | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other 14bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
[1] 13bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
[1]
Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other Investments 7,014us-gaap_OtherInvestments
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
7,310us-gaap_OtherInvestments
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
Total Financial Assets 8,700,391bx_TotalFinancialAssetsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
9,021,438bx_TotalFinancialAssetsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
Securities Sold, Not Yet Purchased 162,111us-gaap_SecurityOwnedAndSoldNotYetPurchasedFairValueSecuritySoldNotYetPurchased
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
85,878us-gaap_SecurityOwnedAndSoldNotYetPurchasedFairValueSecuritySoldNotYetPurchased
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
Total Financial Liabilities 207,902us-gaap_FinancialLiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
115,049us-gaap_FinancialLiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
Level 2 | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Equity Securities 87,343bx_EquitySecuritiesFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 114,115bx_EquitySecuritiesFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Partnership and LLC Interests 183,675bx_PartnershipAndLlcInterestsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 187,140bx_PartnershipAndLlcInterestsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Debt Instruments 1,473,038us-gaap_DebtInstrumentFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 1,502,314us-gaap_DebtInstrumentFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Investments of Consolidated Funds 7,480,837bx_InvestmentsOfConsolidatedFunds
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 7,818,427bx_InvestmentsOfConsolidatedFunds
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Level 2 | Investments Of Consolidated Blackstone Funds | Corporate Loans    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Corporate Loans 5,387,924bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
[1] 5,691,517bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
[1]
Level 2 | Blackstone's Treasury Cash Management Strategies    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Debt Instruments 1,158,707us-gaap_DebtInstrumentFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
1,141,301us-gaap_DebtInstrumentFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Other 51,618bx_OtherAssetsAtFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
50,850bx_OtherAssetsAtFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Total Blackstone's Treasury Cash Management Strategies 1,210,325bx_InvestmentsInTreasuryCashManagementStrategies
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
1,192,151bx_InvestmentsInTreasuryCashManagementStrategies
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Level 2 | Corporate Bonds | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Corporate Bonds 322,696bx_AssetsOfConsolidatedCloVehiclesCorporateBondsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateBondSecuritiesMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 292,690bx_AssetsOfConsolidatedCloVehiclesCorporateBondsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateBondSecuritiesMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Level 2 | Foreign Currency Contracts    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Net Investment Hedges - Foreign Currency Contracts   523us-gaap_NetInvestmentHedgeDerivativeAssetsAtFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
Net Investment Hedges - Foreign Currency Contracts 408us-gaap_NetInvestmentHedgeDerivativeLiabilitiesAtFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
[1]  
Level 2 | Foreign Currency Contracts | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 1,647us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
2,798us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
Freestanding Derivatives, Liabilities 2,593us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
681us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
Level 2 | Foreign Currency Contracts | Investments Of Consolidated Blackstone Funds | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 5,118us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 8,915us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Level 2 | Interest Rate Contracts | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 260us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
144us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
Freestanding Derivatives, Liabilities 4,645us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
3,233us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
Level 2 | Interest Rate Contracts | Investments Of Consolidated Blackstone Funds | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 2,033us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 2,281us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= us-gaap_InterestRateContractMember
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Level 2 | Credit Default Swaps | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Assets 308us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
85us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
Freestanding Derivatives, Liabilities 1,464us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
868us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
Level 2 | Other | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other 19,010bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
[1] 19,455bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
[1]
Level 2 | Liabilities of Consolidated CLO Vehicles | Foreign Currency Contracts | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Liabilities 36,138us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
[1] 21,875us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_ForeignExchangeContractMember
[1]
Level 2 | Liabilities of Consolidated CLO Vehicles | Credit Default Swaps | Freestanding Derivatives    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Freestanding Derivatives, Liabilities 543us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
[1] 2,514us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis
= bx_FreestandingDerivativesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= bx_CreditDefaultSwapsMember
[1]
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other Investments 111,676us-gaap_OtherInvestments
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
107,210us-gaap_OtherInvestments
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
Total Financial Assets 3,803,853bx_TotalFinancialAssetsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
3,740,693bx_TotalFinancialAssetsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
Total Financial Liabilities 6,933,747us-gaap_FinancialLiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
6,797,104us-gaap_FinancialLiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
Level 3 | Loans And Receivables    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Loans and Receivables 40,691us-gaap_LoansReceivableFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= bx_LoansAndReceivablesMember
40,397us-gaap_LoansReceivableFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= bx_LoansAndReceivablesMember
Level 3 | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment Funds 1,170,378bx_InvestmentFundsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 1,103,210bx_InvestmentFundsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Equity Securities 186,687bx_EquitySecuritiesFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 179,311bx_EquitySecuritiesFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Partnership and LLC Interests 1,562,341bx_PartnershipAndLlcInterestsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 1,496,422bx_PartnershipAndLlcInterestsFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Debt Instruments 86,561us-gaap_DebtInstrumentFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 105,970us-gaap_DebtInstrumentFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Investments of Consolidated Funds 3,576,575bx_InvestmentsOfConsolidatedFunds
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1] 3,498,033bx_InvestmentsOfConsolidatedFunds
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
[1]
Level 3 | Investments Of Consolidated Blackstone Funds | Corporate Loans    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Corporate Loans 514,245bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
[1] 588,075bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
[1]
Level 3 | Blackstone's Treasury Cash Management Strategies    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Debt Instruments 64,816us-gaap_DebtInstrumentFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
84,894us-gaap_DebtInstrumentFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Other 10,095bx_OtherAssetsAtFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
10,159bx_OtherAssetsAtFairValue
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Total Blackstone's Treasury Cash Management Strategies 74,911bx_InvestmentsInTreasuryCashManagementStrategies
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
95,053bx_InvestmentsInTreasuryCashManagementStrategies
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_BlackstoneTreasuryCashManagementStrategiesMember
Level 3 | Other | Investments Of Consolidated Blackstone Funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other 56,363bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
[1] 25,045bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ dei_LegalEntityAxis
= bx_InvestmentsOfConsolidatedBlackstoneFundsMember
/ us-gaap_UnderlyingAssetClassAxis
= us-gaap_CollateralizedSecuritiesOtherMember
[1]
Level 3 | Liabilities of Consolidated CLO Vehicles | Senior Secured Notes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair value of Notes 6,587,954us-gaap_NotesPayableFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_SeniorNotesMember
[1] 6,448,352us-gaap_NotesPayableFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
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[1]
Level 3 | Liabilities of Consolidated CLO Vehicles | Subordinated Notes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair value of Notes $ 345,793us-gaap_NotesPayableFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByLiabilityClassAxis
= bx_LiabilitiesOfConsolidatedCloVehiclesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_SeniorSubordinatedNotesMember
[1] $ 348,752us-gaap_NotesPayableFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByLiabilityClassAxis
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/ us-gaap_InvestmentTypeAxis
= us-gaap_SeniorSubordinatedNotesMember
[1]
[1] Pursuant to GAAP consolidation guidance, the Partnership is required to consolidate all VIEs in which it has been identified as the primary beneficiary, including certain CLO vehicles, and other funds in which a consolidated entity of the Partnership, as the general partner of the fund, is presumed to have control. While the Partnership is required to consolidate certain funds, including CLO vehicles, for GAAP purposes, the Partnership has no ability to utilize the assets of these funds and there is no recourse to the Partnership for their liabilities since these are client assets and liabilities.