DERIVATIVES AND HEDGING - Fair Value of Derivatives of Consolidated Funds (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets
Fair Value	$ 17,354	$ 17,946
Liabilities
Fair Value	(46,565)	(12,383)
Consolidated Funds
Assets
Fair Value	12,259	6,733
Liabilities
Fair Value	(46,158)	(11,847)
Foreign-currency forward contracts | Consolidated Funds
Assets
Fair Value	9,063	5,062
Liabilities
Fair Value	(1,563)	(886)
Total-return and interest-rate and credit default swaps | Consolidated Funds
Assets
Fair Value	718	1,162
Liabilities
Fair Value	(37,933)	(4,335)
Options and futures | Consolidated Funds
Assets
Fair Value	2,478	509
Liabilities
Fair Value	(36)
Warrants | Consolidated Funds
Liabilities
Fair Value	(6,626)	(6,626)
Not Designated as Hedging Instrument | Consolidated Funds
Assets
Notional	612,765	438,170
Fair Value	12,259	6,733
Liabilities
Notional	(200,604)	(52,099)
Fair Value	(46,627)	(11,847)
Not Designated as Hedging Instrument | Foreign-currency forward contracts | Consolidated Funds
Assets
Notional	381,809	210,868
Fair Value	9,063	5,062
Liabilities
Notional	(18,099)	(24,845)
Fair Value	(1,563)	(886)
Not Designated as Hedging Instrument | Total-return and interest-rate and credit default swaps | Consolidated Funds
Assets
Notional	8,291	13,727
Fair Value	718	1,162
Liabilities
Notional	(182,441)	(27,254)
Fair Value	(37,933)	(4,335)
Not Designated as Hedging Instrument | Options and futures | Consolidated Funds
Assets
Notional	222,665	213,575
Fair Value	2,478	509
Liabilities
Notional	(64)	0
Fair Value	(36)	0
Not Designated as Hedging Instrument | Warrants | Consolidated Funds
Assets
Notional	0	0
Fair Value	0	0
Liabilities
Notional	0	0
Fair Value	$ (7,095)	$ (6,626)