FAIR VALUE (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Investments measured at NAV
FAIR VALUE
Investments, at fair value	$ 361,402	$ 339,243
Assets, at fair value	361,402	339,243
Investments measured at NAV \| Private Investment Partnership Interests
FAIR VALUE
Investments, at fair value	361,402	339,243
Parent Company
FAIR VALUE
Investments, at fair value	473,806	446,779
Derivative assets, at fair value	1,038	1,339
Assets, at fair value	474,844	448,118
Derivative liabilities, at fair value	(2,468)	(390)
Debt obligation	471,274	389,120
Parent Company \| Interest rate contracts
FAIR VALUE
Derivative liabilities, at fair value	(66)	(214)
Parent Company \| Foreign exchange contracts
FAIR VALUE
Derivative assets, at fair value	1,038	1,339
Derivative liabilities, at fair value	(2,402)	(176)
Parent Company \| Interest rate swaps
FAIR VALUE
Derivative liabilities, at fair value		(214)
Parent Company \| Fixed Income Investments [Member]
FAIR VALUE
Investments, at fair value	54,118	55,752
Parent Company \| Collateralized loan obligation
FAIR VALUE
Investments, at fair value	54,118	55,752
Parent Company \| Equity securities
FAIR VALUE
Investments, at fair value	83	81
Parent Company \| Private Investment Partnership Interests
FAIR VALUE
Investments, at fair value	419,605	390,946
Parent Company \| Level I
FAIR VALUE
Investments, at fair value	83	81
Assets, at fair value	83	81
Parent Company \| Level I \| Equity securities
FAIR VALUE
Investments, at fair value	83	81
Parent Company \| Level II
FAIR VALUE
Derivative assets, at fair value	1,038	1,339
Assets, at fair value	1,038	1,339
Derivative liabilities, at fair value	(2,468)	(390)
Parent Company \| Level II \| Interest rate contracts
FAIR VALUE
Derivative liabilities, at fair value	(66)
Parent Company \| Level II \| Foreign exchange contracts
FAIR VALUE
Derivative assets, at fair value	1,038	1,339
Derivative liabilities, at fair value	(2,402)	(176)
Parent Company \| Level II \| Interest rate swaps
FAIR VALUE
Derivative liabilities, at fair value		(214)
Parent Company \| Level III
FAIR VALUE
Investments, at fair value	112,321	107,455
Assets, at fair value	112,321	107,455
Parent Company \| Level III \| Fixed Income Investments [Member]
FAIR VALUE
Investments, at fair value	54,118	55,752
Parent Company \| Level III \| Collateralized loan obligation
FAIR VALUE
Investments, at fair value	54,118	55,752
Parent Company \| Level III \| Private Investment Partnership Interests
FAIR VALUE
Investments, at fair value	58,203	51,703
Consolidated Funds
FAIR VALUE
Investments, at fair value	2,553,169	2,559,783
Assets, at fair value	2,553,169
Derivative liabilities, at fair value	(5,858)	(10,676)
Loan obligations of debt	(2,167,773)
Liabilities, at fair value	(2,173,631)	(2,185,028)
Consolidated Funds \| Securities Sold Short
FAIR VALUE
Loan obligations of debt		(2,174,352)
Consolidated Funds \| Other Derivatives
FAIR VALUE
Derivative liabilities, at fair value	(4,127)	(10,307)
Consolidated Funds \| Equity contracts
FAIR VALUE
Derivative assets, at fair value	155	159
Consolidated Funds \| Foreign exchange contracts
FAIR VALUE
Derivative liabilities, at fair value	(1,731)	(369)
Consolidated Funds \| Fixed Income Investments [Member]
FAIR VALUE
Investments, at fair value	2,261,156	2,251,120
Consolidated Funds \| Corporate Bonds
FAIR VALUE
Investments, at fair value	233,738	235,312
Consolidated Funds \| Loans
FAIR VALUE
Investments, at fair value	2,021,156	2,009,687
Consolidated Funds \| Collateralized loan obligation
FAIR VALUE
Investments, at fair value	6,262	6,121
Consolidated Funds \| Equity securities
FAIR VALUE
Investments, at fair value	188,237	221,602
Consolidated Funds \| Private Investment Partnership Interests
FAIR VALUE
Investments, at fair value	103,621	86,902
Consolidated Funds \| Other
FAIR VALUE
Investments, at fair value	155	159
Consolidated Funds \| Level I
FAIR VALUE
Investments, at fair value		76,033
Assets, at fair value	44,692
Consolidated Funds \| Level I \| Equity securities
FAIR VALUE
Investments, at fair value	44,692	76,033
Consolidated Funds \| Level II
FAIR VALUE
Investments, at fair value		2,017,549
Assets, at fair value	2,050,842
Derivative liabilities, at fair value	(1,731)	(369)
Loan obligations of debt	(2,167,773)
Liabilities, at fair value	(2,169,504)	(369)
Consolidated Funds \| Level II \| Foreign exchange contracts
FAIR VALUE
Derivative liabilities, at fair value	(1,731)	(369)
Consolidated Funds \| Level II \| Fixed Income Investments [Member]
FAIR VALUE
Investments, at fair value	2,048,947	2,001,630
Consolidated Funds \| Level II \| Corporate Bonds
FAIR VALUE
Investments, at fair value	127,926	126,289
Consolidated Funds \| Level II \| Loans
FAIR VALUE
Investments, at fair value	1,921,021	1,875,341
Consolidated Funds \| Level II \| Equity securities
FAIR VALUE
Investments, at fair value	1,740	15,760
Consolidated Funds \| Level II \| Other
FAIR VALUE
Investments, at fair value	155	159
Consolidated Funds \| Level III
FAIR VALUE
Investments, at fair value		466,201
Assets, at fair value	457,635	466,201
Derivative liabilities, at fair value	(4,127)	(10,307)
Liabilities, at fair value	(4,127)	(2,184,659)
Consolidated Funds \| Level III \| Securities Sold Short
FAIR VALUE
Loan obligations of debt		(2,174,352)
Consolidated Funds \| Level III \| Other Derivatives
FAIR VALUE
Derivative liabilities, at fair value	(4,127)	(10,307)
Consolidated Funds \| Level III \| Fixed Income Investments [Member]
FAIR VALUE
Investments, at fair value	212,209	249,490
Consolidated Funds \| Level III \| Corporate Bonds
FAIR VALUE
Investments, at fair value	105,812	109,023
Consolidated Funds \| Level III \| Loans
FAIR VALUE
Investments, at fair value	100,135	134,346
Consolidated Funds \| Level III \| Collateralized loan obligation
FAIR VALUE
Investments, at fair value	6,262	6,121
Consolidated Funds \| Level III \| Equity securities
FAIR VALUE
Investments, at fair value	141,805	129,809
Consolidated Funds \| Level III \| Private Investment Partnership Interests
FAIR VALUE
Investments, at fair value	$ 103,621	$ 86,902

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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