FAIR VALUE - Consolidated Funds Summary of Changes in Fair Value of Level III Investments (Details) - Consolidated Funds - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 3,603,942	$ 2,390,273
Initial consolidation of funds	2,962
Transfers into Level III	266,905	5,580
Transfers out of Level III	(336,819)	(5,451)
Purchases	281,462	335,934
Sales	(165,039)	(63,287)
Realized gain (losses), net	(82,921)	21,656
Unrealized appreciation (depreciation), net	104,646	(17,511)
Ending balance	3,675,138	2,667,194
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	97,454	(17,654)
Corporate debt – bank debt
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	1,721,888	702,497
Initial consolidation of funds	2,962
Transfers into Level III	190,733	159
Transfers out of Level III	(255,229)	(4,473)
Purchases	169,907	278,808
Sales	(85,491)	(2,863)
Realized gain (losses), net	(328)	31
Unrealized appreciation (depreciation), net	15,060	(11,843)
Ending balance	1,759,502	962,316
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	11,488	(11,987)
Corporate debt – all other
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	260,292	219,503
Initial consolidation of funds	0
Transfers into Level III	15,359	5,421
Transfers out of Level III	(65,930)	(978)
Purchases	1,408	657
Sales	(37,144)	0
Realized gain (losses), net	915	(228)
Unrealized appreciation (depreciation), net	1,363	2,789
Ending balance	176,263	227,164
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	(37)	2,789
Equities – common stock
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	846,773	777,198
Initial consolidation of funds	0
Transfers into Level III	54,678	0
Transfers out of Level III	(15,660)	0
Purchases	86,233	44,992
Sales	(42,358)	(25,201)
Realized gain (losses), net	11,149	12,868
Unrealized appreciation (depreciation), net	6,006	(48)
Ending balance	946,821	809,809
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	3,784	(49)
Equities – Preferred Stock
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	599,636	616,604
Initial consolidation of funds	0
Transfers into Level III	0	0
Transfers out of Level III	0	0
Purchases	16,966	4,191
Sales	(46)	(35,223)
Realized gain (losses), net	(94,657)	8,987
Unrealized appreciation (depreciation), net	83,972	(11,959)
Ending balance	605,871	582,600
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	83,972	(11,959)
Real estate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	175,353	74,471
Initial consolidation of funds	0
Transfers into Level III	6,135	0
Transfers out of Level III	0	0
Purchases	6,948	7,286
Sales	0	0
Realized gain (losses), net	0	(2)
Unrealized appreciation (depreciation), net	(1,755)	3,550
Ending balance	186,681	85,305
Net change in unrealized appreciation (depreciation) attributable to assets still held at end of period	$ (1,753)	$ 3,552