Related Party Transactions - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Related Party Transaction [Line Items]
Founder's, other senior managing directors' and employees' investments	$ 1,100,000,000		$ 1,100,000,000		$ 1,000,000,000
Founder's, other senior managing directors' and employees' share of the Net Income Attributable to Redeemable Non-Controlling Interests	40,000,000	43,900,000	135,700,000	144,500,000
Management and Advisory Fees, Net from Affiliates	107,615,000	48,906,000	262,990,000	169,029,000
Interest from loans to affiliates	1,000,000	900,000	2,100,000	2,700,000
Partnership Unit to Blackstone Common Unit ratio			1
Cash saving in tax receivable agreements, percentage			85.00%
Expected future payments under the tax receivable agreements	1,200,000,000		1,200,000,000
Expected future payments under the tax receivable agreements in years			15 years
After-tax net present value estimated payments	$ 388,100,000		$ 388,100,000
After-tax net present value discount rate assumption	15.00%		15.00%