Financial Data of Segments (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total Management and Advisory Fees, Net	$ 608,906	$ 616,768
Performance Fees Realized - Carried Interest	230,909	1,207,594
Performance Fees Realized - Incentive Fees	28,419	29,638
Performance Fees Unrealized - Carried Interest	47,586	373,840
Performance Fees Unrealized - Incentive Fees	7,579	62,036
Total Performance Fees	314,493	1,673,108
Investment Income (Loss), Realized	(12,001)	187,930
Investment Income (Loss), Unrealized	3,493	18,273
Total Investment Income (Loss)	(8,508)	206,203
Interest and Dividend Revenue	23,075	21,920
Other	(5,612)	(5,641)
Total Revenues	932,354	2,512,358
Compensation and Benefits Compensation	346,003	559,559
Performance Fee Compensation - Realized Carried Interest	58,504	292,248
Performance Fee Compensation - Realized Incentive Fees	14,124	12,227
Performance Fee Compensation - Unrealized Carried Interest	30,001	74,380
Performance Fee Compensation - Unrealized Incentive Fees	3,448	24,961
Total Compensation and Benefits	452,080	963,375
Total Expenses	617,710	1,142,568
Economic Income (Loss)	333,786	1,463,345
Segment Assets	22,050,904		$ 22,526,080
Operating Segments
Segment Reporting Information [Line Items]
Management and Advisory Fees, Base Management Fees	586,703	516,397
Management and Advisory Fees, Advisory Fees	481	84,238
Management and Advisory Fees, Transaction and Other Fees, Net	46,118	37,073
Management and Advisory Fees, Management Fee Offsets	(20,101)	(17,945)
Total Management and Advisory Fees, Net	613,201	619,763
Performance Fees Realized - Carried Interest	230,909	1,207,594
Performance Fees Realized - Incentive Fees	28,450	29,670
Performance Fees Unrealized - Carried Interest	47,606	373,852
Performance Fees Unrealized - Incentive Fees	7,100	62,620
Total Performance Fees	314,065	1,673,736
Investment Income (Loss), Realized	(10,101)	107,792
Investment Income (Loss), Unrealized	(16,549)	81,849
Total Investment Income (Loss)	(26,650)	189,641
Interest and Dividend Revenue	35,081	30,451
Other	(6,248)	(4,872)
Total Revenues	929,449	2,508,719
Compensation and Benefits Compensation	287,403	329,838
Performance Fee Compensation - Realized Carried Interest	58,503	292,248
Performance Fee Compensation - Realized Incentive Fees	14,123	12,227
Performance Fee Compensation - Unrealized Carried Interest	30,001	74,380
Performance Fee Compensation - Unrealized Incentive Fees	3,448	24,961
Total Compensation and Benefits	393,478	733,654
Other Operating Expenses	148,526	143,282
Total Expenses	542,004	876,936
Economic Income (Loss)	387,445	1,631,783
Segment Assets	17,124,534
Operating Segments | Private Equity Segment
Segment Reporting Information [Line Items]
Management and Advisory Fees, Base Management Fees	130,648	108,383
Management and Advisory Fees, Advisory Fees	481	2,429
Management and Advisory Fees, Transaction and Other Fees, Net	8,439	20,359
Management and Advisory Fees, Management Fee Offsets	(6,848)	(4,949)
Total Management and Advisory Fees, Net	132,720	126,222
Performance Fees Realized - Carried Interest	30,282	382,978
Performance Fees Unrealized - Carried Interest	73,875	566,822
Total Performance Fees	104,157	949,800
Investment Income (Loss), Realized	(15,357)	44,816
Investment Income (Loss), Unrealized	15,440	31,487
Total Investment Income (Loss)	83	76,303
Interest and Dividend Revenue	9,849	7,618
Other	(1,587)	(1,825)
Total Revenues	245,222	1,158,118
Compensation and Benefits Compensation	80,274	71,072
Performance Fee Compensation - Realized Carried Interest	15,427	39,482
Performance Fee Compensation - Unrealized Carried Interest	9,296	178,120
Total Compensation and Benefits	104,997	288,674
Other Operating Expenses	48,063	38,875
Total Expenses	153,060	327,549
Economic Income (Loss)	92,162	830,569
Segment Assets	5,390,618
Operating Segments | Real Estate Segment
Segment Reporting Information [Line Items]
Management and Advisory Fees, Base Management Fees	199,907	152,348
Management and Advisory Fees, Transaction and Other Fees, Net	35,794	15,216
Management and Advisory Fees, Management Fee Offsets	(3,595)	(4,866)
Total Management and Advisory Fees, Net	232,106	162,698
Performance Fees Realized - Carried Interest	200,627	811,249
Performance Fees Realized - Incentive Fees	4,069	723
Performance Fees Unrealized - Carried Interest	(11,522)	(181,019)
Performance Fees Unrealized - Incentive Fees	9,765	6,069
Total Performance Fees	202,939	637,022
Investment Income (Loss), Realized	12,975	71,344
Investment Income (Loss), Unrealized	(2,137)	37,510
Total Investment Income (Loss)	10,838	108,854
Interest and Dividend Revenue	13,188	9,997
Other	(1,909)	(3,977)
Total Revenues	457,162	914,594
Compensation and Benefits Compensation	100,578	84,834
Performance Fee Compensation - Realized Carried Interest	43,076	246,496
Performance Fee Compensation - Realized Incentive Fees	2,133	356
Performance Fee Compensation - Unrealized Carried Interest	27,703	(98,084)
Performance Fee Compensation - Unrealized Incentive Fees	4,158	2,575
Total Compensation and Benefits	177,648	236,177
Other Operating Expenses	48,097	40,143
Total Expenses	225,745	276,320
Economic Income (Loss)	231,417	638,274
Segment Assets	7,320,885
Operating Segments | Hedge Fund Solutions Segment
Segment Reporting Information [Line Items]
Management and Advisory Fees, Base Management Fees	130,158	130,637
Management and Advisory Fees, Transaction and Other Fees, Net	543	25
Management and Advisory Fees, Management Fee Offsets		(280)
Total Management and Advisory Fees, Net	130,701	130,382
Performance Fees Realized - Incentive Fees	2,684	10,516
Performance Fees Unrealized - Carried Interest	32
Performance Fees Unrealized - Incentive Fees	(2,935)	47,427
Total Performance Fees	(219)	57,943
Investment Income (Loss), Realized	(4,745)	(10,375)
Investment Income (Loss), Unrealized	(12,291)	4,483
Total Investment Income (Loss)	(17,036)	(5,892)
Interest and Dividend Revenue	5,296	3,949
Other	(1,388)	(1,607)
Total Revenues	117,354	184,775
Compensation and Benefits Compensation	54,169	56,104
Performance Fee Compensation - Realized Incentive Fees	1,863	3,470
Performance Fee Compensation - Unrealized Incentive Fees	(1,195)	15,651
Total Compensation and Benefits	54,837	75,225
Other Operating Expenses	26,146	21,206
Total Expenses	80,983	96,431
Economic Income (Loss)	36,371	88,344
Segment Assets	1,762,700
Operating Segments | Credit Segment
Segment Reporting Information [Line Items]
Management and Advisory Fees, Base Management Fees	125,990	125,029
Management and Advisory Fees, Transaction and Other Fees, Net	1,342	1,457
Management and Advisory Fees, Management Fee Offsets	(9,658)	(7,850)
Total Management and Advisory Fees, Net	117,674	118,636
Performance Fees Realized - Carried Interest		13,367
Performance Fees Realized - Incentive Fees	21,697	18,431
Performance Fees Unrealized - Carried Interest	(14,779)	(11,951)
Performance Fees Unrealized - Incentive Fees	270	9,124
Total Performance Fees	7,188	28,971
Investment Income (Loss), Realized	(2,974)	2,237
Investment Income (Loss), Unrealized	(17,561)	6,887
Total Investment Income (Loss)	(20,535)	9,124
Interest and Dividend Revenue	6,748	5,651
Other	(1,364)	3,493
Total Revenues	109,711	165,875
Compensation and Benefits Compensation	52,382	49,877
Performance Fee Compensation - Realized Carried Interest		6,270
Performance Fee Compensation - Realized Incentive Fees	10,127	8,401
Performance Fee Compensation - Unrealized Carried Interest	(6,998)	(5,656)
Performance Fee Compensation - Unrealized Incentive Fees	485	6,735
Total Compensation and Benefits	55,996	65,627
Other Operating Expenses	26,220	21,836
Total Expenses	82,216	87,463
Economic Income (Loss)	27,495	78,412
Segment Assets	$ 2,650,331
Operating Segments | Financial Advisory Segment
Segment Reporting Information [Line Items]
Management and Advisory Fees, Advisory Fees		81,809
Management and Advisory Fees, Transaction and Other Fees, Net		16
Total Management and Advisory Fees, Net		81,825
Investment Income (Loss), Realized		(230)
Investment Income (Loss), Unrealized		1,482
Total Investment Income (Loss)		1,252
Interest and Dividend Revenue		3,236
Other		(956)
Total Revenues		85,357
Compensation and Benefits Compensation		67,951
Total Compensation and Benefits		67,951
Other Operating Expenses		21,222
Total Expenses		89,173
Economic Income (Loss)		$ (3,816)