v2.4.0.8
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 9 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2014
Sep. 30, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Balance, Beginning of Period $ 3,468,422 $ 3,045,964 $ 3,555,138 $ 3,076,466
Transfer In Due to Consolidation and Acquisition     276,806 [1] 11,960 [1]
Transfer Out Due to Deconsolidation (64,634) (96) (335,357) (152,823)
Transfer In to Level III 181,784 [2] 235,012 [2] 302,358 [2] 693,489 [2]
Transfer Out of Level III (222,021) [2] (273,239) [2] (335,724) [2] (382,421) [2]
Purchases 392,213 499,804 877,286 1,036,328
Sales (250,709) (308,421) (946,634) (1,238,281)
Settlements (649) 2,040 (1,594) 490
Realized Gains (Losses), Net 21,349 13,704 9,800 9,602
Changes in Unrealized Gains (Losses) Included in Earnings Related to Investments Still Held at the Reporting Date (37,127) 66,691 86,549 226,649
Balance, End of Period 3,488,628 3,281,459 3,488,628 3,281,459
Investments Of Consolidated Funds
        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Balance, Beginning of Period 3,245,040 2,890,319 3,358,752 3,017,699
Transfer In Due to Consolidation and Acquisition     276,806 [1]  
Transfer Out Due to Deconsolidation (64,634) (96) (335,357) (152,823)
Transfer In to Level III 161,332 [2] 226,144 [2] 273,934 [2] 684,621 [2]
Transfer Out of Level III (212,108) [2] (270,059) [2] (315,067) [2] (377,527) [2]
Purchases 303,044 349,209 561,043 673,179
Sales (201,346) (154,446) (700,970) (959,115)
Realized Gains (Losses), Net 21,344 13,861 10,344 (4,913)
Changes in Unrealized Gains (Losses) Included in Earnings Related to Investments Still Held at the Reporting Date (29,039) 67,127 94,148 240,938
Balance, End of Period 3,223,633 3,122,059 3,223,633 3,122,059
Loans And Receivables
        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Balance, Beginning of Period 42,725 107,731 137,788 30,663
Purchases 69,255 127,370 162,899 233,890
Sales (42,261) (138,937) (230,324) (168,399)
Settlements (526) 2,293 (1,170) 2,312
Realized Gains (Losses), Net       43
Changes in Unrealized Gains (Losses) Included in Earnings Related to Investments Still Held at the Reporting Date 601 (380) 601 (432)
Balance, End of Period 69,794 98,077 69,794 98,077
Other
        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Balance, Beginning of Period 180,657 [3] 47,914 [3] 58,598 [3] 28,104 [3]
Transfer In Due to Consolidation and Acquisition       11,960 [1],[3]
Transfer In to Level III 20,452 [2],[3] 8,868 [2],[3] 28,424 [2],[3] 8,868 [2],[3]
Transfer Out of Level III (9,913) [2],[3] (3,180) [2],[3] (20,657) [2],[3] (4,894) [2],[3]
Purchases 19,914 [3] 23,225 [3] 153,344 [3] 129,259 [3]
Sales (7,102) [3] (15,038) [3] (15,340) [3] (110,767) [3]
Settlements (123) [3] (253) [3] (424) [3] (1,822) [3]
Realized Gains (Losses), Net 5 [3] (157) [3] (544) [3] 14,472 [3]
Changes in Unrealized Gains (Losses) Included in Earnings Related to Investments Still Held at the Reporting Date (8,689) [3] (56) [3] (8,200) [3] (13,857) [3]
Balance, End of Period $ 195,201 [3] $ 61,323 [3] $ 195,201 [3] $ 61,323 [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.