v2.4.1.9

Performance Fees Allocated to Funds (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
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Mar. 31, 2015
Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
Performance Fees, December 31, 2014 | $ 6,337,045 bx_PerformanceFeesReceivable
Performance Fees Allocated as a Result of Changes in Fund Fair Values | 1,643,458 bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues
Foreign Exchange Loss | (43,947)bx_ForeignCurrencyExchangeGainLoss
Fund Distributions | (1,094,158)bx_FundDistributions
Performance Fees, March 31, 2015 | 6,842,398 bx_PerformanceFeesReceivable
Private Equity Segment |
Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
Performance Fees, December 31, 2014 | 2,215,584 bx_PerformanceFeesReceivable / us-gaap_StatementBusinessSegmentsAxis = bx_PrivateEquitySegmentMember
Performance Fees Allocated as a Result of Changes in Fund Fair Values | 949,515 bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues / us-gaap_StatementBusinessSegmentsAxis = bx_PrivateEquitySegmentMember
Fund Distributions | (402,044)bx_FundDistributions / us-gaap_StatementBusinessSegmentsAxis = bx_PrivateEquitySegmentMember
Performance Fees, March 31, 2015 | 2,763,055 bx_PerformanceFeesReceivable / us-gaap_StatementBusinessSegmentsAxis = bx_PrivateEquitySegmentMember
Real Estate Segment |
Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
Performance Fees, December 31, 2014 | 3,721,751 bx_PerformanceFeesReceivable / us-gaap_StatementBusinessSegmentsAxis = bx_RealEstateSegmentMember
Performance Fees Allocated as a Result of Changes in Fund Fair Values | 674,475 bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues / us-gaap_StatementBusinessSegmentsAxis = bx_RealEstateSegmentMember
Foreign Exchange Loss | (43,947)bx_ForeignCurrencyExchangeGainLoss / us-gaap_StatementBusinessSegmentsAxis = bx_RealEstateSegmentMember
Fund Distributions | (666,321)bx_FundDistributions / us-gaap_StatementBusinessSegmentsAxis = bx_RealEstateSegmentMember
Performance Fees, March 31, 2015 | 3,685,958 bx_PerformanceFeesReceivable / us-gaap_StatementBusinessSegmentsAxis = bx_RealEstateSegmentMember
Hedge Fund Solutions Segment |
Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
Performance Fees, December 31, 2014 | 15,031 bx_PerformanceFeesReceivable / us-gaap_StatementBusinessSegmentsAxis = bx_HedgeFundSolutionsSegmentMember
Performance Fees Allocated as a Result of Changes in Fund Fair Values | 12,353 bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues / us-gaap_StatementBusinessSegmentsAxis = bx_HedgeFundSolutionsSegmentMember
Fund Distributions | (12,696)bx_FundDistributions / us-gaap_StatementBusinessSegmentsAxis = bx_HedgeFundSolutionsSegmentMember
Performance Fees, March 31, 2015 | 14,688 bx_PerformanceFeesReceivable / us-gaap_StatementBusinessSegmentsAxis = bx_HedgeFundSolutionsSegmentMember
Credit Segment |
Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
Performance Fees, December 31, 2014 | 384,679 bx_PerformanceFeesReceivable / us-gaap_StatementBusinessSegmentsAxis = bx_CreditSegmentMember
Performance Fees Allocated as a Result of Changes in Fund Fair Values | 7,115 bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues / us-gaap_StatementBusinessSegmentsAxis = bx_CreditSegmentMember
Fund Distributions | (13,097)bx_FundDistributions / us-gaap_StatementBusinessSegmentsAxis = bx_CreditSegmentMember
Performance Fees, March 31, 2015 | $ 378,697 bx_PerformanceFeesReceivable / us-gaap_StatementBusinessSegmentsAxis = bx_CreditSegmentMember

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