Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Related Party Transaction [Line Items]
Founder's, other senior managing directors' and employees' investments	$ 821,200		$ 821,200		$ 1,000,000
Founder's, other senior managing directors' and employees' share of the Net Income Attributable to Redeemable Non-Controlling Interests	31,600	$ 50,800	81,100	$ 95,700
Management and Advisory Fees, Net from Affiliates	28,831	81,343	76,943	155,375
Interest from loans to affiliates	1,200	$ 1,000	$ 3,300	$ 1,100
Partnership Unit to Blackstone Common Unit ratio			100.00%
Cash saving in tax receivable agreements, percentage			85.00%
Expected future payments under the tax receivable agreements	1,300,000		$ 1,300,000
Expected future payments under the tax receivable agreements in years			15 years
After-tax net present value estimated payments	$ 392,400		$ 392,400
After-tax net present value discount rate assumption	15.00%		15.00%