FAIR VALUE - Consolidated Funds Summary of Changes in Fair Value of Level III Investments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 25,624	$ 0	$ 25,750	$ 0
Ending balance	26,581	0	26,581	0
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	957	0	831	0
Consolidated Funds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	206,990	28,015,703	27,217,707	26,291,698
Cumulative-effect adjustment from adoption of accounting guidance			(27,012,584)
Transfers into Level III	0	88,981	37,933	527,139
Transfers out of Level III	(1,962)	(664,435)	(42,670)	(812,088)
Purchases	2,397	1,981,399	9,537	3,745,958
Sales	(11,411)	(1,725,985)	(13,693)	(2,290,026)
Realized gains (losses), net	89	547,364	115	541,851
Unrealized appreciation (depreciation), net	(330)	(217,503)	(572)	20,992
Ending balance	195,773	28,025,524	195,773	28,025,524
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	(2,051)	(407,637)	(572)	300,819
Consolidated Funds | Corporate debt – bank debt
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	200,811	1,573,508	1,871,375	1,555,656
Cumulative-effect adjustment from adoption of accounting guidance			(1,672,305)
Transfers into Level III	0	9,598	37,535	116,533
Transfers out of Level III	(1,962)	(42,396)	(42,670)	(145,998)
Purchases	2,239	42,721	9,378	224,751
Sales	(10,886)	(185,407)	(12,872)	(340,767)
Realized gains (losses), net	89	10,604	115	25,407
Unrealized appreciation (depreciation), net	(382)	(9,351)	(647)	(36,305)
Ending balance	189,909	1,399,277	189,909	1,399,277
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	(2,103)	(12,235)	(647)	(17,619)
Consolidated Funds | Corporate debt – all other
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	1,853	2,772,859	3,009,164	2,750,661
Cumulative-effect adjustment from adoption of accounting guidance			(3,007,287)
Transfers into Level III	0	17,208	0	17,208
Transfers out of Level III		(78,250)	0	(110,084)
Purchases	1	314,898	2	566,463
Sales		(84,407)	0	(163,351)
Realized gains (losses), net		(35,773)	0	(32,499)
Unrealized appreciation (depreciation), net	36	8,839	11	(113,024)
Ending balance	1,890	2,915,374	1,890	2,915,374
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	36	(76,879)	11	(43,928)
Consolidated Funds | Equities – common stock
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	4,326	10,156,394	8,729,202	9,056,579
Cumulative-effect adjustment from adoption of accounting guidance			(8,725,026)
Transfers into Level III	0	50,976	398	377,563
Transfers out of Level III		(523,407)	0	(523,423)
Purchases	157	341,691	157	1,194,127
Sales	(525)	(349,498)	(821)	(442,219)
Realized gains (losses), net		73,211	0	(66,126)
Unrealized appreciation (depreciation), net	16	(46,358)	64	106,508
Ending balance	3,974	9,703,009	3,974	9,703,009
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	16	(12,504)	64	192,837
Consolidated Funds | Equities – preferred stock
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	1,381,135	1,363,542	1,320,752
Cumulative-effect adjustment from adoption of accounting guidance			(1,363,542)
Transfers into Level III	0	11,199	0	15,835
Transfers out of Level III		(20,382)	0	(32,583)
Purchases		147,396	0	205,128
Sales		(2,760)	0	(54,947)
Realized gains (losses), net		(1,153)	0	37,384
Unrealized appreciation (depreciation), net		144,303	0	168,169
Ending balance	0	1,659,738	0	1,659,738
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	0	1,253	0	109,462
Consolidated Funds | Real estate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	9,728,967	9,655,270	9,216,056
Cumulative-effect adjustment from adoption of accounting guidance			(9,655,270)
Transfers into Level III	0	0	0	0
Transfers out of Level III		0	0	0
Purchases		658,056	0	949,574
Sales		(890,418)	0	(985,355)
Realized gains (losses), net		432,658	0	479,057
Unrealized appreciation (depreciation), net		(356,361)	0	(86,430)
Ending balance	0	9,572,902	0	9,572,902
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	0	(335,645)	0	92,476
Consolidated Funds | Real estate loan portfolios
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	2,406,252	2,597,405	2,399,105
Cumulative-effect adjustment from adoption of accounting guidance			(2,597,405)
Transfers into Level III	0	0	0	0
Transfers out of Level III		0	0	0
Purchases		476,637	0	605,915
Sales		(213,495)	0	(303,387)
Realized gains (losses), net		67,817	0	98,628
Unrealized appreciation (depreciation), net		42,261	0	(20,789)
Ending balance	0	2,779,472	0	2,779,472
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	0	27,778	0	(35,272)
Consolidated Funds | Swaps
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	(6,988)	(8,251)	(10,687)
Cumulative-effect adjustment from adoption of accounting guidance			8,251
Transfers into Level III	0	0	0	0
Transfers out of Level III		0	0	0
Purchases		0	0	0
Sales		0	0	0
Realized gains (losses), net		0	0	0
Unrealized appreciation (depreciation), net		(1,656)	0	2,043
Ending balance	0	(8,644)	0	(8,644)
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	0	(225)	0	2,043
Consolidated Funds | Other:
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	3,576	0	3,576
Cumulative-effect adjustment from adoption of accounting guidance			0
Transfers into Level III	0	0	0	0
Transfers out of Level III		0	0	0
Purchases		0	0	0
Sales		0	0	0
Realized gains (losses), net		0	0	0
Unrealized appreciation (depreciation), net		820	0	820
Ending balance	0	4,396	0	4,396
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	$ 0	$ 820	$ 0	$ 820