DERIVATIVES - Fair Values of Derivatives Reported on Condensed Consolidated Statements of Financial Condition (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Derivatives, Fair Value [Line Items]
Derivative assets, fair value	$ 1,865	$ 4,373
Derivative assets, amounts not netted: cash collateral	(82)	0
Derivative assets, amounts not netted: securities collateral	0	0
Derivative assets, fair value, total	1,279	3,787
Derivative assets, notional amount	179,697	360,748
Derivative liabilities, fair value	172,645	289,442
Derivative liabilities, amounts not netted: cash collateral	(89)	(1,132)
Derivative liabilities, amounts not netted: securities collateral	0	0
Derivative liabilities, fair value, total	172,051	273,148
Derivative liabilities, notional	369,133	531,202
Forward foreign currency exchange rate contracts
Derivatives, Fair Value [Line Items]
Derivative assets, fair value	598	4,248
Derivative assets fair value counterparty and cash collateral netting	(321)	(461)
Derivative assets, notional amount	96,561	359,717
Derivative liabilities, fair value	753	1,068
Derivative liabilities, fair value, counterparty and cash collateral netting	(322)	(460)
Derivative liabilities, notional	187,928	167,115
Total return swaps and other
Derivatives, Fair Value [Line Items]
Derivative assets, fair value	1,267	125
Derivative assets fair value counterparty and cash collateral netting	(183)	(125)
Derivative assets, notional amount	83,136	1,031
Derivative liabilities, fair value	183	17,527
Derivative liabilities, fair value, counterparty and cash collateral netting	(183)	(14,702)
Derivative liabilities, notional	17,125	116,239
LFI and other similar deferred compensation arrangements
Derivatives, Fair Value [Line Items]
Derivative assets, fair value	0	0
Derivative assets, notional amount	0	0
Derivative liabilities, fair value	171,709	270,847
Derivative liabilities, notional	164,080	247,848
Net derivatives in "other assets" and "other liabilities"
Derivatives, Fair Value [Line Items]
Derivative assets, net derivatives	1,361	3,787
Derivative liabilities, net derivatives	$ 172,140	$ 274,280