v2.4.1.9
Summary of Fair Value by Strategy Type Alongside Consolidated Funds of Hedge Funds' Remaining Unfunded Commitments and Ability to Redeem Such Investments (Detail) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]  
Fair Value $ 1,303,717us-gaap_AlternativeInvestmentsFairValueDisclosure
Unfunded Commitments 1,415us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments
Diversified Instruments  
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]  
Fair Value 186,184us-gaap_AlternativeInvestmentsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= bx_DiversifiedInstrumentsMember		 [1]
Unfunded Commitments 1,415us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments
/ us-gaap_InvestmentTypeAxis
= bx_DiversifiedInstrumentsMember		 [1]
Credit Driven  
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]  
Fair Value 345,381us-gaap_AlternativeInvestmentsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= bx_CreditDrivenMember		 [2]
Event Driven  
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]  
Fair Value 197,613us-gaap_AlternativeInvestmentsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= bx_EventDrivenMember		 [3]
Equity  
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]  
Fair Value 369,338us-gaap_AlternativeInvestmentsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= bx_EquitiesMember		 [4]
Commodities  
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]  
Fair Value 64,911us-gaap_AlternativeInvestmentsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= bx_CommoditiesMember		 [5]
Private Equity  
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]  
Fair Value $ 140,290us-gaap_AlternativeInvestmentsFairValueDisclosure
/ us-gaap_InvestmentTypeAxis
= bx_PrivateEquityMember		 [6]
[1] Diversified Instruments include investments in funds that invest across multiple strategies. Investments representing 81% of the fair value of the investments in this category may not be redeemed at, or within three months of, the reporting date. Investments representing 13% of the fair value of the investments in this category represent investments in hedge funds that are in the process of liquidating. Distributions from these funds will be received as underlying investments are liquidated. The time at which this redemption restriction may lapse cannot be estimated. The remaining 6% of investments in this category are redeemable as of the reporting date. As of the reporting date, the investee fund manager had elected to side-pocket 7% of Blackstone's investments in this category.
[2] The Credit Driven category includes investments in hedge funds that invest primarily in domestic and international bonds. Investments representing 66% of the fair value of the investments in this category may not be redeemed at, or within three months of, the reporting date. Investments representing 30% of the fair value of the investments in this category are redeemable as of the reporting date. Investments representing 3% of the total fair value in the credit driven category are subject to redemption restrictions such as the investee fund manager's ability to limit the amount of redemptions. The remaining 1% of the investments in this category are in the process of liquidating. Distributions from these funds will be received as underlying investments are liquidated. The time at which this redemption restriction may lapse cannot be estimated.
[3] The Event Driven category includes investments in hedge funds whose primary investing strategy is to identify certain event-driven investments. Withdrawals are not permitted in this category. Distributions will be received as the underlying investments are liquidated.
[4] The Equity category includes investments in hedge funds that invest primarily in domestic and international equity securities. Withdrawals are generally not permitted for the investments in this category. Distributions will be received as the underlying investments are liquidated.
[5] The Commodities category includes investments in commodities-focused funds that primarily invest in futures and physical-based commodity driven strategies. Withdrawals are not permitted for investments representing 96% of the fair value of investments in this category. Distributions will be received as the underlying investments are liquidated. The remaining 4% of the fair value of the investments in this category may not be redeemed at, or within three months of, the reporting date.
[6] The Private Equity category includes investments in private equity funds that primarily invest in private equity, revenue interests and other private investments. Withdrawals are not permitted for investments in this category.