Summary of Changes in Financial Assets Measured at Fair Value for Which Level III Inputs Were Used (Detail) (Level 3, USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Balance, Beginning of Period	$ 3,555,138		$ 3,076,466
Transfer In Due to Consolidation and Acquisition	276,806	[1]
Transfer In (Out) Due to Deconsolidation	(83,867)		(86,599)
Transfer In to Level III	199,286	[2]	207,476	[2]
Transfer Out of Level III	(245,317)	[2]	(322,764)	[2]
Purchases	318,491		238,615
Sales	(451,568)		(198,649)
Settlements	(1,325)		(1,891)
Realized Gains, Net	17,117		8,934
Changes in Unrealized Gains (Losses) Included in Earnings Related to Investments Still Held at the Reporting Date	26,545		82,625
Balance, End of Period	3,611,306		3,004,213
Investments Of Consolidated Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Balance, Beginning of Period	3,358,752		3,017,699
Transfer In Due to Consolidation and Acquisition	276,806	[1]
Transfer In (Out) Due to Deconsolidation	(83,867)		(98,559)
Transfer In to Level III	195,607	[2]	207,476	[2]
Transfer Out of Level III	(244,308)	[2]	(322,764)	[2]
Purchases	159,613		172,968
Sales	(290,782)		(129,725)
Realized Gains, Net	17,015		8,042
Changes in Unrealized Gains (Losses) Included in Earnings Related to Investments Still Held at the Reporting Date	23,986		82,160
Balance, End of Period	3,412,822		2,937,297
Loans And Receivables
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Balance, Beginning of Period	137,788		30,663
Purchases	81,241		2,873
Sales	(156,719)		(29,462)
Settlements	(1,170)		(332)
Realized Gains, Net			43
Changes in Unrealized Gains (Losses) Included in Earnings Related to Investments Still Held at the Reporting Date	433		82
Balance, End of Period	61,573		3,867
Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Balance, Beginning of Period	58,598	[3]	28,104	[3]
Transfer In (Out) Due to Deconsolidation			11,960	[3]
Transfer In to Level III	3,679	[2],[3]
Transfer Out of Level III	(1,009)	[2],[3]
Purchases	77,637	[3]	62,774	[3]
Sales	(4,067)	[3]	(39,462)	[3]
Settlements	(155)	[3]	(1,559)	[3]
Realized Gains, Net	102	[3]	849	[3]
Changes in Unrealized Gains (Losses) Included in Earnings Related to Investments Still Held at the Reporting Date	2,126	[3]	383	[3]
Balance, End of Period	$ 136,911	[3]	$ 63,049	[3]

[1] Represents the transfer into Level III of financial assets and liabilities as a result of the consolidation of certain fund entities.

[2] Transfers in and out of Level III financial assets and liabilities were due to changes in the observability of inputs used in the valuation of such assets and liabilities.

[3] Represents Blackstone's Treasury Cash Management Strategies and Other Investments.