INVESTMENTS - Net Gains (Losses) from Investment Activities of Consolidated Funds (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Gain (Loss) on Investments [Line Items]
Net realized gain on consolidated funds’ investments	$ 6,682	$ 857,548	$ 10,083	$ 1,332,378
Consolidated Funds
Gain (Loss) on Investments [Line Items]
Net change in unrealized appreciation (depreciation) on consolidated funds’ investments	(5,301)	(1,418,385)	(25,973)	(910,902)
Consolidated Funds \| Not Designated as Hedging Instrument
Gain (Loss) on Investments [Line Items]
Net realized gain on consolidated funds’ investments	6,682	857,548	10,083	1,332,378
Net change in unrealized appreciation (depreciation) on consolidated funds’ investments	(5,301)	(1,418,385)	(25,973)	(910,902)
Consolidated Funds \| Investments and other financial instruments \| Not Designated as Hedging Instrument
Gain (Loss) on Investments [Line Items]
Net realized gain on consolidated funds’ investments	8,651	707,427	12,322	875,226
Net change in unrealized appreciation (depreciation) on consolidated funds’ investments	17,740	(1,018,970)	27,423	(461,655)
Consolidated Funds \| Measurement alternative guidance for CLOs \| Not Designated as Hedging Instrument
Gain (Loss) on Investments [Line Items]
Net realized gain on consolidated funds’ investments	0	0	0	0
Net change in unrealized appreciation (depreciation) on consolidated funds’ investments	(24,172)	0	(52,374)	0
Consolidated Funds \| Foreign-currency forward contracts \| Not Designated as Hedging Instrument
Gain (Loss) on Investments [Line Items]
Net realized gain on consolidated funds’ investments	(298)	175,334	(500)	471,310
Net change in unrealized appreciation (depreciation) on consolidated funds’ investments	849	(339,448)	457	(319,064)
Consolidated Funds \| Total-return and interest-rate swaps \| Not Designated as Hedging Instrument
Gain (Loss) on Investments [Line Items]
Net realized gain on consolidated funds’ investments	(907)	(2,248)	(890)	(7,174)
Net change in unrealized appreciation (depreciation) on consolidated funds’ investments	222	(56,008)	(1,396)	(116,226)
Consolidated Funds \| Options and futures \| Not Designated as Hedging Instrument
Gain (Loss) on Investments [Line Items]
Net realized gain on consolidated funds’ investments	(764)	(21,778)	(849)	(3,977)
Net change in unrealized appreciation (depreciation) on consolidated funds’ investments	60	(5,150)	(83)	(16,299)
Consolidated Funds \| Swaptions \| Not Designated as Hedging Instrument
Gain (Loss) on Investments [Line Items]
Net realized gain on consolidated funds’ investments	0	(1,187)	0	(3,007)
Net change in unrealized appreciation (depreciation) on consolidated funds’ investments	$ 0	$ 1,191	$ 0	$ 2,342

The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.3(a))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 325
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6485959&loc=d3e22529-158502

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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