Summary of Aggregate Notional Amount and Fair Value of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	$ 2,018,439	$ 719,650
Derivative Liabilities, Notional	1,546,624	1,425,901
Derivative Assets, Fair Value	6,019	15,009
Derivative Liabilities, Fair Value	21,507	30,528
Net Investment Hedges \| Foreign Currency Contracts
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	53,627	62,078
Derivative Liabilities, Notional	138
Derivative Assets, Fair Value	319	523
Derivative Liabilities, Fair Value	1
Freestanding Derivatives
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	1,964,812	657,572
Derivative Liabilities, Notional	1,546,486	1,425,901
Derivative Assets, Fair Value	5,700	14,486
Derivative Liabilities, Fair Value	21,506	30,528
Freestanding Derivatives \| Credit Default Swap
Derivatives, Fair Value [Line Items]
Derivative Assets, Fair Value		85
Derivative Liabilities, Fair Value	2,411
Freestanding Derivatives \| Blackstone - Other \| Credit Default Swap
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional		19,500
Derivative Liabilities, Notional	19,250	56,000
Derivative Assets, Fair Value		85
Derivative Liabilities, Fair Value	2,411	868
Freestanding Derivatives \| Investments Of Consolidated Blackstone Funds \| Credit Default Swap
Derivatives, Fair Value [Line Items]
Derivative Liabilities, Notional	108,786	91,372
Derivative Liabilities, Fair Value	6,275	2,514
Freestanding Derivatives \| Foreign Currency Contracts \| Blackstone - Other
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	158,684	192,163
Derivative Liabilities, Notional	271,891	148,873
Derivative Assets, Fair Value	2,088	2,798
Derivative Liabilities, Fair Value	2,042	681
Freestanding Derivatives \| Foreign Currency Contracts \| Investments Of Consolidated Blackstone Funds
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	124,595	199,364
Derivative Liabilities, Notional	92,094	250,244
Derivative Assets, Fair Value	1,400	8,915
Derivative Liabilities, Fair Value	6,490	21,875
Freestanding Derivatives \| Interest Rate Contracts \| Blackstone - Other
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional	1,681,533	223,886
Derivative Liabilities, Notional	1,054,465	879,412
Derivative Assets, Fair Value	2,212	407
Derivative Liabilities, Fair Value	$ 4,288	4,590
Freestanding Derivatives \| Interest Rate Contracts \| Investments Of Consolidated Blackstone Funds
Derivatives, Fair Value [Line Items]
Derivative Assets, Notional		22,659
Derivative Assets, Fair Value		$ 2,281

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
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