Financial Assets and Liabilities at Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment Funds	$ 970,477	[1]	$ 897,843	[1]
Equity Securities	388,403	[1]	375,662	[1]
Partnership and LLC Interests	1,447,304	[1]	1,343,458	[1]
Debt Instruments	1,599,570	[1]	1,200,397	[1]
Corporate Loans	7,914,869	[1]	8,466,889	[1]
Corporate Bonds	143,333	[1]	161,382	[1]
Other	29,820	[1]	41,061	[1]
Investments of Consolidated Funds	12,521,552	[1]	12,521,248	[1]
Blackstone's Treasury Cash Management Strategies	996,806		1,104,800
Money Market Funds	196,428		173,781
Freestanding Derivatives, Assets	33,456		44,899
Loans and Receivables	61,573		137,788
Other Investments	116,242		118,804
Total Financial Assets	13,898,281		14,066,764
Freestanding Derivatives - Credit Default Swaps	7,912	[1]
Senior Secured Notes	7,795,523	[1]	8,302,572	[1]
Subordinated Notes	619,188	[1]	610,435	[1]
Freestanding Derivatives - Foreign Currency Contracts	12,197	[1]	10,018	[1]
Total Liabilities of Consolidated Blackstone Funds	8,434,820
Securities Sold, Not Yet Purchased	296,434		76,195
Total Financial Liabilities	8,736,299		9,003,502
Foreign Currency Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives - Foreign Currency Contracts	24,919	[1]	30,830	[1]
Freestanding Derivatives, Assets	846		1,480
Freestanding Derivatives, Liabilities	737		1,015
Interest Rate Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives - Interest Rate Contracts	2,857	[1]	3,726	[1]
Freestanding Derivatives, Assets	4,834		8,521
Freestanding Derivatives, Liabilities	1,545		2,676
Total Return Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives, Assets			342
Credit Default Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives, Liabilities	2,763		591
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities	74,543	[1]	51,147	[1]
Debt Instruments	2,708	[1]
Other	21	[1]	3,477	[1]
Investments of Consolidated Funds	77,272	[1]	54,624	[1]
Blackstone's Treasury Cash Management Strategies	90,586		19,629
Money Market Funds	196,428		173,781
Other Investments	20,873		87,068
Total Financial Assets	389,208		342,525
Total Financial Liabilities	1,502		2,484
Level 1 | Interest Rate Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives, Assets	4,049		7,423
Freestanding Derivatives, Liabilities	1,502		2,484
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities	106,643	[1]	130,816	[1]
Partnership and LLC Interests	163,401	[1]	88,555	[1]
Debt Instruments	1,442,482	[1]	1,154,902	[1]
Corporate Loans	7,147,823	[1]	7,537,661	[1]
Corporate Bonds	143,333	[1]	161,382	[1]
Investments of Consolidated Funds	9,031,458	[1]	9,107,872	[1]
Blackstone's Treasury Cash Management Strategies	857,359		1,041,039
Other Investments	7,319		17,270
Total Financial Assets	9,897,767		10,169,101
Freestanding Derivatives - Credit Default Swaps	7,912	[1]
Freestanding Derivatives - Foreign Currency Contracts	12,197	[1]	10,018	[1]
Total Liabilities of Consolidated Blackstone Funds	20,109
Securities Sold, Not Yet Purchased	296,434		76,195
Total Financial Liabilities	320,086		88,011
Level 2 | Foreign Currency Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives - Foreign Currency Contracts	24,919	[1]	30,830	[1]
Freestanding Derivatives, Assets	846		1,480
Freestanding Derivatives, Liabilities	737		1,015
Level 2 | Interest Rate Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives - Interest Rate Contracts	2,857	[1]	3,726	[1]
Freestanding Derivatives, Assets	785		1,098
Freestanding Derivatives, Liabilities	43		192
Level 2 | Total Return Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives, Assets			342
Level 2 | Credit Default Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Freestanding Derivatives, Liabilities	2,763		591
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment Funds	970,477	[1]	897,843	[1]
Equity Securities	207,217	[1]	193,699	[1]
Partnership and LLC Interests	1,283,903	[1]	1,254,903	[1]
Debt Instruments	154,380	[1]	45,495	[1]
Corporate Loans	767,046	[1]	929,228	[1]
Other	29,799	[1]	37,584	[1]
Investments of Consolidated Funds	3,412,822	[1]	3,358,752	[1]
Blackstone's Treasury Cash Management Strategies	48,861		44,132
Loans and Receivables	61,573		137,788
Other Investments	88,050		14,466
Total Financial Assets	3,611,306		3,555,138
Senior Secured Notes	7,795,523	[1]	8,302,572	[1]
Subordinated Notes	619,188	[1]	610,435	[1]
Total Liabilities of Consolidated Blackstone Funds	8,414,711
Total Financial Liabilities	$ 8,414,711		$ 8,913,007

[1] Pursuant to GAAP consolidation guidance, the Partnership is required to consolidate all VIEs in which it has been identified as the primary beneficiary, including certain CLO vehicles, and other funds in which a consolidated entity of the Partnership, as the general partner of the fund, is presumed to have control. While the Partnership is required to consolidate certain funds, including CLO vehicles, for GAAP purposes, the Partnership has no ability to utilize the assets of these funds and there is no recourse to the Partnership for their liabilities since these are client assets and liabilities.