v2.4.1.9

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

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- Definition Assets Of Consolidated CLO Vehicles Corporate Bonds Fair Value Disclosure + References No definition available. + Details
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- Definition Assets Of Consolidated CLO Vehicles Corporate Loans Fair Value Disclosure + References No definition available. + Details
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- Definition Partnership and LLC Interests Fair Value. + References No definition available. + Details
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- Definition Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities. + References No definition available. + Details
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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Glossary Loan -URI http://asc.fasb.org/extlink&oid=6517073 + Details
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- Definition Fair value of all derivative assets designated as hedges of net investment in foreign operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959 + Details
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- Definition Fair value portion of notes payable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19,20,22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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