DERIVATIVES AND HEDGING DERIVATIVES AND HEDGING - Fair Value of Derivatives of Consolidated Funds (Details) - Consolidated Funds - Not Designated as Hedging Instrument - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets
Notional	$ 166,917	$ 107,106
Fair Value	6,890	2,464
Liabilities
Notional	(140,276)	(48,081)
Fair Value	(2,551)	(643)
Foreign-currency forward contracts
Assets
Notional	166,917	95,980
Fair Value	6,890	2,275
Liabilities
Notional	(140,276)	(48,081)
Fair Value	$ (2,551)	(643)
Options and futures
Assets
Notional		11,126
Fair Value		189
Liabilities
Notional		0
Fair Value		$ 0

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=SL51823488-111719

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

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