Realized and Net Change in Unrealized Gains (Losses) on Investments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Gain (Loss) on Investments [Line Items]
Total realized and net change in unrealized gains (losses)	$ (146,639)	$ (375,399)	$ 231,089	$ (546,475)
Consolidated Blackstone Funds
Gain (Loss) on Investments [Line Items]
Realized Gains (Losses)	6,162	121,297	(4,279)	228,052
Net Change in Unrealized Gains (Losses)	(152,801)	(496,696)	235,368	(774,527)
Total realized and net change in unrealized gains (losses)	$ (146,639)	$ (375,399)	$ 231,089	$ (546,475)