INVESTMENTS - Fair Value (Details) $ in Thousands	Jun. 30, 2023 USD ($) investment	Dec. 31, 2022 USD ($) investment
Schedule Of Investments In Marketable Securities [Line Items]
Investments, fair value that exceeds threshold | investment	0	0
Investments, percentage of net assets, threshold percentage	5.00%	5.00%
Consolidated Funds
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 2,772,767	$ 2,098,838
Debt securities, fair value as a percentage of investments of consolidated funds	61.20%	53.70%
Equity securities, fair value	$ 1,666,000	$ 1,735,304
Equity securities, fair value as a percentage of investments of consolidated funds	36.80%	44.40%
Real estate investments, at fair value	$ 88,675	$ 74,471
Real estate, fair value as a percentage of investments of consolidated funds	2.00%	1.90%
Investments, at fair value	$ 4,527,442	$ 3,908,613
Total investments, fair value as a percentage of investments of consolidated funds	100.00%	100.00%
Consolidated Funds | United States:
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 1,885,920	$ 1,318,317
Debt securities, fair value as a percentage of investments of consolidated funds	41.70%	33.60%
Total debt securities, cost	$ 1,975,206	$ 1,437,262
Equity securities, fair value	$ 1,300,283	$ 1,310,735
Equity securities, fair value as a percentage of investments of consolidated funds	28.70%	33.70%
Total equity securities, cost	$ 1,061,469	$ 1,000,922
Real estate investments, at fair value	$ 3,475	$ 1,796
Real estate, fair value as a percentage of investments of consolidated funds	0.10%	0.00%
Real estate securities, cost	$ 3,017	$ 1,797
Consolidated Funds | United States: | Communication services
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 108,658	$ 100,995
Debt securities, fair value as a percentage of investments of consolidated funds	2.40%	2.60%
Equity securities, fair value	$ 69,661	$ 64,621
Equity securities, fair value as a percentage of investments of consolidated funds	1.50%	1.70%
Consolidated Funds | United States: | Consumer discretionary
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 228,762	$ 127,170
Debt securities, fair value as a percentage of investments of consolidated funds	5.10%	3.30%
Equity securities, fair value	$ 134,894	$ 133,104
Equity securities, fair value as a percentage of investments of consolidated funds	3.00%	3.40%
Consolidated Funds | United States: | Consumer staples
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 20,122	$ 23,542
Debt securities, fair value as a percentage of investments of consolidated funds	0.40%	0.60%
Consolidated Funds | United States: | Energy
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 180,288	$ 79,573
Debt securities, fair value as a percentage of investments of consolidated funds	4.00%	2.00%
Equity securities, fair value	$ 433,746	$ 482,984
Equity securities, fair value as a percentage of investments of consolidated funds	9.60%	12.40%
Consolidated Funds | United States: | Financials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 339,478	$ 217,878
Debt securities, fair value as a percentage of investments of consolidated funds	7.50%	5.60%
Equity securities, fair value	$ 185,092	$ 181,980
Equity securities, fair value as a percentage of investments of consolidated funds	4.10%	4.70%
Consolidated Funds | United States: | Health care
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 125,019	$ 111,005
Debt securities, fair value as a percentage of investments of consolidated funds	2.80%	2.80%
Equity securities, fair value	$ 26,164	$ 26,191
Equity securities, fair value as a percentage of investments of consolidated funds	0.60%	0.70%
Consolidated Funds | United States: | Industrials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 254,194	$ 206,479
Debt securities, fair value as a percentage of investments of consolidated funds	5.60%	5.30%
Equity securities, fair value	$ 346,900	$ 308,514
Equity securities, fair value as a percentage of investments of consolidated funds	7.70%	7.90%
Consolidated Funds | United States: | Information technology
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 118,845	$ 136,714
Debt securities, fair value as a percentage of investments of consolidated funds	2.60%	3.50%
Equity securities, fair value	$ 14,914	$ 14,107
Equity securities, fair value as a percentage of investments of consolidated funds	0.30%	0.40%
Consolidated Funds | United States: | Materials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 131,962	$ 118,578
Debt securities, fair value as a percentage of investments of consolidated funds	2.90%	3.00%
Equity securities, fair value	$ 899	$ 899
Equity securities, fair value as a percentage of investments of consolidated funds	0.00%	0.00%
Consolidated Funds | United States: | Real estate
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 137,109	$ 182,643
Debt securities, fair value as a percentage of investments of consolidated funds	3.00%	4.70%
Real estate investments, at fair value	$ 3,475	$ 1,796
Real estate, fair value as a percentage of investments of consolidated funds	0.10%	0.00%
Consolidated Funds | United States: | Utilities
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 16,405	$ 11,850
Debt securities, fair value as a percentage of investments of consolidated funds	0.40%	0.30%
Equity securities, fair value	$ 88,013	$ 98,335
Equity securities, fair value as a percentage of investments of consolidated funds	1.90%	2.50%
Consolidated Funds | United States: | Other
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 225,078	$ 1,890
Debt securities, fair value as a percentage of investments of consolidated funds	5.00%	0.00%
Consolidated Funds | Europe:
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 231,672	$ 217,816
Debt securities, fair value as a percentage of investments of consolidated funds	5.20%	5.50%
Total debt securities, cost	$ 227,604	$ 230,090
Equity securities, fair value	$ 252,478	$ 266,272
Equity securities, fair value as a percentage of investments of consolidated funds	5.60%	6.80%
Total equity securities, cost	$ 233,883	$ 241,129
Real estate investments, at fair value	$ 85,200	$ 72,675
Real estate, fair value as a percentage of investments of consolidated funds	1.90%	1.90%
Real estate securities, cost	$ 81,598	$ 69,100
Consolidated Funds | Europe: | Communication services
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 105,463	$ 103,068
Debt securities, fair value as a percentage of investments of consolidated funds	2.30%	2.60%
Consolidated Funds | Europe: | Consumer discretionary
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 15,929	$ 13,997
Debt securities, fair value as a percentage of investments of consolidated funds	0.40%	0.40%
Equity securities, fair value	$ 94,570	$ 130,868
Equity securities, fair value as a percentage of investments of consolidated funds	2.10%	3.30%
Consolidated Funds | Europe: | Consumer staples
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 1,916	$ 8,024
Debt securities, fair value as a percentage of investments of consolidated funds	0.00%	0.20%
Consolidated Funds | Europe: | Energy
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 1,361	$ 1,097
Debt securities, fair value as a percentage of investments of consolidated funds	0.00%	0.00%
Consolidated Funds | Europe: | Financials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 15,698	$ 35,091
Debt securities, fair value as a percentage of investments of consolidated funds	0.30%	0.90%
Equity securities, fair value	$ 36,250	$ 31,701
Equity securities, fair value as a percentage of investments of consolidated funds	0.80%	0.80%
Consolidated Funds | Europe: | Health care
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 11,439	$ 8,178
Debt securities, fair value as a percentage of investments of consolidated funds	0.30%	0.20%
Equity securities, fair value	$ 3	$ 9
Equity securities, fair value as a percentage of investments of consolidated funds	0.00%	0.00%
Consolidated Funds | Europe: | Industrials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 14,385	$ 12,384
Debt securities, fair value as a percentage of investments of consolidated funds	0.30%	0.30%
Equity securities, fair value	$ 58,661	$ 53,790
Equity securities, fair value as a percentage of investments of consolidated funds	1.30%	1.40%
Consolidated Funds | Europe: | Information technology
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 25,048	$ 4,583
Debt securities, fair value as a percentage of investments of consolidated funds	0.60%	0.10%
Consolidated Funds | Europe: | Materials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 13,441	$ 10,920
Debt securities, fair value as a percentage of investments of consolidated funds	0.30%	0.30%
Equity securities, fair value	$ 24,282	$ 24,282
Equity securities, fair value as a percentage of investments of consolidated funds	0.50%	0.60%
Consolidated Funds | Europe: | Real estate
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 16,494	$ 12,888
Debt securities, fair value as a percentage of investments of consolidated funds	0.40%	0.30%
Equity securities, fair value	$ 38,712	$ 25,622
Equity securities, fair value as a percentage of investments of consolidated funds	0.90%	0.70%
Real estate investments, at fair value	$ 85,200	$ 72,675
Real estate, fair value as a percentage of investments of consolidated funds	1.90%	1.90%
Consolidated Funds | Europe: | Utilities
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 7,947	$ 5,102
Debt securities, fair value as a percentage of investments of consolidated funds	0.20%	0.10%
Consolidated Funds | Europe: | Other
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 2,551	$ 2,484
Debt securities, fair value as a percentage of investments of consolidated funds	0.10%	0.10%
Consolidated Funds | Asia and other:
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 655,175	$ 562,705
Debt securities, fair value as a percentage of investments of consolidated funds	14.40%	14.40%
Total debt securities, cost	$ 680,512	$ 581,467
Equity securities, fair value	$ 113,239	$ 158,297
Equity securities, fair value as a percentage of investments of consolidated funds	2.40%	4.00%
Total equity securities, cost	$ 99,042	$ 722,128
Consolidated Funds | Asia and other: | Communication services
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 853	$ 5,419
Debt securities, fair value as a percentage of investments of consolidated funds	0.00%	0.10%
Consolidated Funds | Asia and other: | Consumer discretionary
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 5,921	$ 5,641
Debt securities, fair value as a percentage of investments of consolidated funds	0.10%	0.20%
Consolidated Funds | Asia and other: | Consumer staples
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 19,615	$ 19,125
Debt securities, fair value as a percentage of investments of consolidated funds	0.40%	0.50%
Consolidated Funds | Asia and other: | Energy
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 8,432	$ 9,163
Debt securities, fair value as a percentage of investments of consolidated funds	0.20%	0.20%
Equity securities, fair value	$ 6,029	$ 7,581
Equity securities, fair value as a percentage of investments of consolidated funds	0.10%	0.20%
Consolidated Funds | Asia and other: | Financials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 7,742	$ 8,344
Debt securities, fair value as a percentage of investments of consolidated funds	0.20%	0.20%
Consolidated Funds | Asia and other: | Health care
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 2,649	$ 2,837
Debt securities, fair value as a percentage of investments of consolidated funds	0.10%	0.10%
Consolidated Funds | Asia and other: | Industrials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 3,980	$ 3,754
Debt securities, fair value as a percentage of investments of consolidated funds	0.10%	0.10%
Equity securities, fair value	$ 70,031	$ 113,270
Equity securities, fair value as a percentage of investments of consolidated funds	1.50%	2.90%
Consolidated Funds | Asia and other: | Information technology
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 953	$ 695
Debt securities, fair value as a percentage of investments of consolidated funds	0.00%	0.00%
Consolidated Funds | Asia and other: | Materials
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 161,356	$ 113,784
Debt securities, fair value as a percentage of investments of consolidated funds	3.60%	2.90%
Consolidated Funds | Asia and other: | Real estate
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 439,532	$ 328,343
Debt securities, fair value as a percentage of investments of consolidated funds	9.70%	8.40%
Equity securities, fair value	$ 32,916	$ 32,916
Equity securities, fair value as a percentage of investments of consolidated funds	0.70%	0.80%
Consolidated Funds | Asia and other: | Utilities
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 4,142	$ 5,602
Debt securities, fair value as a percentage of investments of consolidated funds	0.10%	0.10%
Equity securities, fair value	$ 4,263	$ 4,530
Equity securities, fair value as a percentage of investments of consolidated funds	0.10%	0.10%
Consolidated Funds | Asia and other: | Other
Schedule Of Investments In Marketable Securities [Line Items]
Debt securities, fair value	$ 0	$ 59,998
Debt securities, fair value as a percentage of investments of consolidated funds	0.00%	1.50%