Summary of Aggregate Notional Amount and Fair Value of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	$ 971,807	$ 2,018,439
Derivative Liabilities, Notional	1,054,104	1,546,624
Derivative Assets, Fair Value	15,385	6,019
Derivative Liabilities, Fair Value	18,998	21,507
Net Investment Hedges \| Foreign Currency Contracts
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	6,087	53,627
Derivative Liabilities, Notional	53,191	138
Derivative Assets, Fair Value	9	319
Derivative Liabilities, Fair Value	1,677	1
Freestanding Derivatives
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	965,720	1,964,812
Derivative Liabilities, Notional	1,000,913	1,546,486
Derivative Assets, Fair Value	15,376	5,700
Derivative Liabilities, Fair Value	17,321	21,506
Freestanding Derivatives \| Credit Default Swap
Derivatives, Fair Value [Line Items]
Derivative Assets, Fair Value	12
Derivative Liabilities, Fair Value		2,411
Freestanding Derivatives \| Blackstone \| Credit Default Swap
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	2,275
Derivative Liabilities, Notional		19,250
Derivative Assets, Fair Value	12
Derivative Liabilities, Fair Value		2,411
Freestanding Derivatives \| Investments Of Consolidated Blackstone Funds \| Credit Default Swap
Derivatives, Fair Value [Line Items]
Derivative Liabilities, Notional	122,682	108,786
Derivative Liabilities, Fair Value	7,647	6,275
Freestanding Derivatives \| Foreign Currency Contracts \| Blackstone
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	163,031	158,684
Derivative Liabilities, Notional	127,891	271,891
Derivative Assets, Fair Value	2,902	2,088
Derivative Liabilities, Fair Value	1,063	2,042
Freestanding Derivatives \| Foreign Currency Contracts \| Investments Of Consolidated Blackstone Funds
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	197,087	124,595
Derivative Liabilities, Notional	26,253	92,094
Derivative Assets, Fair Value	11,562	1,400
Derivative Liabilities, Fair Value	2,846	6,490
Freestanding Derivatives \| Interest Rate Contracts \| Blackstone
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	603,327	1,681,533
Derivative Liabilities, Notional	724,087	1,054,465
Derivative Assets, Fair Value	900	2,212
Derivative Liabilities, Fair Value	$ 5,765	$ 4,288

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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