v2.4.1.9
Condensed Consolidated Statements of Changes in Partners' Capital (USD $)
In Thousands, except Share data
Total
USD ($)
Partners' Capital
USD ($)
Appropriated Partners' Capital
USD ($)
Accumulated Other Comprehensive Income
USD ($)
Total
USD ($)
Non-Controlling Interests in Consolidated Entities
USD ($)
Non-Controlling Interests in Blackstone Holdings
USD ($)
Total Partners' Capital
USD ($)
Redeemable NonControlling Interests in Consolidated Entities
USD ($)
Common Units
Beginning Balance at Dec. 31, 2013                 $ 1,950,442us-gaap_RedeemableNoncontrollingInterestEquityFairValue
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Beginning Balance at Dec. 31, 2013   6,002,592us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
300,708us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
3,466us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedOtherComprehensiveIncomeMember
6,306,766us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
2,464,047us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
3,656,416us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
12,427,229us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Beginning Balance, Units at Dec. 31, 2013                   572,592,279us-gaap_PartnersCapitalAccountUnits
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CapitalUnitsMember
Net Delivery of Vested Blackstone Holdings Partnership Units and Blackstone Common Units                   4,759,747us-gaap_PartnersCapitalAccountUnitsSaleOfUnits
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CapitalUnitsMember
Conversion of Blackstone Holdings Partnership Units to Blackstone Common Units, Units                   6,739,766us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CapitalUnitsMember
Transition and Acquisition Adjustments Relating to Consolidation of CLO Entities     8,398bx_TransitionAndAcquisitionAdjustmentsRelatingToConsolidationOfCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
  8,398bx_TransitionAndAcquisitionAdjustmentsRelatingToConsolidationOfCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    8,398bx_TransitionAndAcquisitionAdjustmentsRelatingToConsolidationOfCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Consolidation of Fund Entity           4,511bx_NoncontrollingInterestAttributableToConsolidationOfInvestmentManagementFunds
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
  4,511bx_NoncontrollingInterestAttributableToConsolidationOfInvestmentManagementFunds
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
30,922bx_NoncontrollingInterestAttributableToConsolidationOfInvestmentManagementFunds
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Net Income 654,875us-gaap_ProfitLoss 265,617us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    265,617us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
43,961us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
299,505us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
609,083us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
45,792us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Allocation of Income / (Losses) of Consolidated CLO Entities     (39,019)bx_AllocationOfIncomeLossOfConsolidatedCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
  (39,019)bx_AllocationOfIncomeLossOfConsolidatedCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
39,019bx_AllocationOfIncomeLossOfConsolidatedCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
       
Currency Translation Adjustment (1,166)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax     (1,048)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedOtherComprehensiveIncomeMember
(1,048)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
(118)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
  (1,166)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Allocation of Currency Translation Adjustment of Consolidated CLO Entities     (118)bx_AllocationOfCurrencyTranslationAdjustmentOfConsolidatedCollateralizedLoanObligations
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
  (118)bx_AllocationOfCurrencyTranslationAdjustmentOfConsolidatedCollateralizedLoanObligations
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
118bx_AllocationOfCurrencyTranslationAdjustmentOfConsolidatedCollateralizedLoanObligations
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
       
Reclassification of Currency Translation Adjustment Due to Deconsolidation of CLO Entities   (2,695)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    (2,695)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    (2,695)us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Capital Contributions           147,862us-gaap_PartnersCapitalAccountContributions
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
  147,862us-gaap_PartnersCapitalAccountContributions
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
282,641us-gaap_PartnersCapitalAccountContributions
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Capital Distributions   (341,318)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    (341,318)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
(135,987)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
(367,544)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
(844,849)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
(133,443)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Transfer of Non-Controlling Interests in Consolidated Entities           (212)bx_TransferOfNonControllingInterestsInConsolidatedEntitiesFunds
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
  (212)bx_TransferOfNonControllingInterestsInConsolidatedEntitiesFunds
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Purchase of Interests from Certain Non-Controlling Interest Holders   (6)bx_PurchaseOfInterestsFromCertainNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    (6)bx_PurchaseOfInterestsFromCertainNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    (6)bx_PurchaseOfInterestsFromCertainNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Deferred Tax Effects Resulting from Acquisition of Ownership Interests from Non-Controlling Interest Holders   12,645bx_DeferredTaxEffectsResultingFromAcquisitionOfOwnershipInterestsFromNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    12,645bx_DeferredTaxEffectsResultingFromAcquisitionOfOwnershipInterestsFromNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    12,645bx_DeferredTaxEffectsResultingFromAcquisitionOfOwnershipInterestsFromNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Equity-Based Compensation   142,117us-gaap_PartnersCapitalAccountUnitBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    142,117us-gaap_PartnersCapitalAccountUnitBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
  133,128us-gaap_PartnersCapitalAccountUnitBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
275,245us-gaap_PartnersCapitalAccountUnitBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Relinquished with Deconsolidation and Liquidation of Partnership     (35,460)us-gaap_DeconsolidationGainOrLossAmount
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
  (35,460)us-gaap_DeconsolidationGainOrLossAmount
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
(55)us-gaap_DeconsolidationGainOrLossAmount
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
  (35,515)us-gaap_DeconsolidationGainOrLossAmount
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Net Delivery of Vested Blackstone Holdings Partnership Units and Blackstone Common Units   (19,129)us-gaap_PartnersCapitalAccountSaleOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    (19,129)us-gaap_PartnersCapitalAccountSaleOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    (19,129)us-gaap_PartnersCapitalAccountSaleOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Excess Tax Benefits Related to Equity-Based Compensation, Net   14,006us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    14,006us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    14,006us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Change in The Blackstone Group L.P.'s Ownership Interest (10,354)bx_ChangeOfParentOwnershipInterest (10,354)bx_ChangeOfParentOwnershipInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    (10,354)bx_ChangeOfParentOwnershipInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
  10,354bx_ChangeOfParentOwnershipInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
     
Conversion of Blackstone Holdings Partnership Units to Blackstone Common Units   45,050us-gaap_StockIssuedDuringPeriodValueConversionOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    45,050us-gaap_StockIssuedDuringPeriodValueConversionOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
  (45,050)us-gaap_StockIssuedDuringPeriodValueConversionOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
     
Ending Balance at Mar. 31, 2014                 2,176,354us-gaap_RedeemableNoncontrollingInterestEquityFairValue
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Ending Balance at Mar. 31, 2014   6,108,525us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
234,509us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
2,418us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedOtherComprehensiveIncomeMember
6,345,452us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
2,563,146us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
3,686,809us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
12,595,407us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Ending Balance, Units at Mar. 31, 2014                   584,091,792us-gaap_PartnersCapitalAccountUnits
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CapitalUnitsMember
Beginning Balance at Dec. 31, 2014 2,441,854us-gaap_RedeemableNoncontrollingInterestEquityFairValue               2,441,854us-gaap_RedeemableNoncontrollingInterestEquityFairValue
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Beginning Balance at Dec. 31, 2014 14,891,693us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest 6,999,830us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
81,301us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
(20,864)us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedOtherComprehensiveIncomeMember
7,060,267us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
3,415,356us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
4,416,070us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
14,891,693us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Beginning Balance, Units at Dec. 31, 2014                   595,624,855us-gaap_PartnersCapitalAccountUnits
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CapitalUnitsMember
Net Delivery of Vested Blackstone Holdings Partnership Units and Blackstone Common Units                   7,956,871us-gaap_PartnersCapitalAccountUnitsSaleOfUnits
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CapitalUnitsMember
Conversion of Blackstone Holdings Partnership Units to Blackstone Common Units, Units                   5,603,820us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CapitalUnitsMember
Consolidation of Fund Entity                     
Net Income 1,484,258us-gaap_ProfitLoss 629,448us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    629,448us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
153,222us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
645,230us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
1,427,900us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
56,358us-gaap_ProfitLoss
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Allocation of Income / (Losses) of Consolidated CLO Entities     51,658bx_AllocationOfIncomeLossOfConsolidatedCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
  51,658bx_AllocationOfIncomeLossOfConsolidatedCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
(51,658)bx_AllocationOfIncomeLossOfConsolidatedCloEntities
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
       
Currency Translation Adjustment (50,271)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax     (21,150)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedOtherComprehensiveIncomeMember
(21,150)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
(29,121)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
  (50,271)us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Allocation of Currency Translation Adjustment of Consolidated CLO Entities     (29,121)bx_AllocationOfCurrencyTranslationAdjustmentOfConsolidatedCollateralizedLoanObligations
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
  (29,121)bx_AllocationOfCurrencyTranslationAdjustmentOfConsolidatedCollateralizedLoanObligations
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
29,121bx_AllocationOfCurrencyTranslationAdjustmentOfConsolidatedCollateralizedLoanObligations
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
       
Capital Contributions            141,668us-gaap_PartnersCapitalAccountContributions
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
  141,668us-gaap_PartnersCapitalAccountContributions
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
178,838us-gaap_PartnersCapitalAccountContributions
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Capital Distributions   (482,249)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    (482,249)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
(243,615)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
(488,711)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
(1,214,575)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
(167,003)us-gaap_PartnersCapitalAccountDistributions
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Transfer of Non-Controlling Interests in Consolidated Entities            (10,163)bx_TransferOfNonControllingInterestsInConsolidatedEntitiesFunds
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
  (10,163)bx_TransferOfNonControllingInterestsInConsolidatedEntitiesFunds
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Deferred Tax Effects Resulting from Acquisition of Ownership Interests from Non-Controlling Interest Holders   9,113bx_DeferredTaxEffectsResultingFromAcquisitionOfOwnershipInterestsFromNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    9,113bx_DeferredTaxEffectsResultingFromAcquisitionOfOwnershipInterestsFromNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    9,113bx_DeferredTaxEffectsResultingFromAcquisitionOfOwnershipInterestsFromNonControllingInterestHolders
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Equity-Based Compensation   130,134us-gaap_PartnersCapitalAccountUnitBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    130,134us-gaap_PartnersCapitalAccountUnitBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
  122,236us-gaap_PartnersCapitalAccountUnitBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
252,370us-gaap_PartnersCapitalAccountUnitBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Net Delivery of Vested Blackstone Holdings Partnership Units and Blackstone Common Units   (27,632)us-gaap_PartnersCapitalAccountSaleOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    (27,632)us-gaap_PartnersCapitalAccountSaleOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    (27,632)us-gaap_PartnersCapitalAccountSaleOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Excess Tax Benefits Related to Equity-Based Compensation, Net   23,834us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    23,834us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
    23,834us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Change in The Blackstone Group L.P.'s Ownership Interest 68,361bx_ChangeOfParentOwnershipInterest 68,361bx_ChangeOfParentOwnershipInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    68,361bx_ChangeOfParentOwnershipInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
  (68,361)bx_ChangeOfParentOwnershipInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
     
Conversion of Blackstone Holdings Partnership Units to Blackstone Common Units   46,123us-gaap_StockIssuedDuringPeriodValueConversionOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
    46,123us-gaap_StockIssuedDuringPeriodValueConversionOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
  (46,123)us-gaap_StockIssuedDuringPeriodValueConversionOfUnits
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
     
Ending Balance at Mar. 31, 2015 2,510,047us-gaap_RedeemableNoncontrollingInterestEquityFairValue               2,510,047us-gaap_RedeemableNoncontrollingInterestEquityFairValue
/ us-gaap_StatementEquityComponentsAxis
= bx_RedeemableNonControllingInterestsInConsolidatedEntitiesMember
 
Ending Balance at Mar. 31, 2015 $ 15,443,937us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest $ 7,396,962us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_PartnerCapitalMember
$ 103,838us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_AppropriatedPartnersCapitalMember
$ (42,014)us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedOtherComprehensiveIncomeMember
$ 7,458,786us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalMember
$ 3,404,810us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestsInConsolidatedEntitiesMember
$ 4,580,341us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_NonControllingInterestInBlackstoneHoldingsMember
$ 15,443,937us-gaap_PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
/ us-gaap_StatementEquityComponentsAxis
= bx_TotalPartnersCapitalIncludingNonControllingInterestsMember
   
Ending Balance, Units at Mar. 31, 2015                   609,185,546us-gaap_PartnersCapitalAccountUnits
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CapitalUnitsMember