SEGMENT REPORTING - Adjusted Net Income (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenues:
Management fees	$ 195,015	$ 50,923	$ 393,568	$ 101,742
Incentive income	87,701	564	143,638	564
Total revenues	282,716	51,487	537,206	102,306
Expenses:
Compensation and benefits	(103,002)	(107,750)	(211,407)	(217,893)
Equity-based compensation	(14,726)	(16,083)	(28,622)	(27,789)
Incentive income compensation	(35,461)	(35,211)	(45,268)	(102,103)
General and administrative	(32,949)	(33,488)	(80,780)	(40,068)
Depreciation and amortization	(4,048)	(3,107)	(8,209)	(5,999)
Total expenses	(191,648)	(245,929)	(376,832)	(481,903)
Interest expense, net of interest income	(26,730)	(52,742)	(54,435)	(99,311)
Other income (expense), net	5,548	2,863	11,349	7,557
Adjusted net income	142,645	85,279	247,670	235,305
Investment Management
Revenues:
Management fees	197,450	190,197	398,720	380,292
Incentive income	87,647	61,148	184,235	214,027
Investment income	47,725	23,365	62,802	76,823
Total revenues	332,822	274,710	645,757	671,142
Expenses:
Compensation and benefits	(99,173)	(104,767)	(203,443)	(213,648)
Equity-based compensation	(12,445)	(11,901)	(23,148)	(18,924)
Incentive income compensation	(35,407)	(29,554)	(85,156)	(119,656)
General and administrative	(30,600)	(30,335)	(62,081)	(59,902)
Depreciation and amortization	(3,048)	(2,105)	(6,208)	(3,996)
Total expenses	(180,673)	(178,662)	(380,036)	(416,126)
Adjusted net income before interest and other income (expense)	152,149	96,048	265,721	255,016
Interest expense, net of interest income	(7,977)	(8,782)	(16,659)	(17,715)
Other income (expense), net	(1,527)	(1,987)	(1,392)	(1,996)
Adjusted net income	$ 142,645	$ 85,279	$ 247,670	$ 235,305