SEGMENT REPORTING - Adjusted Net Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Revenues:
Management fees	$ 56,786	[1]	$ 30,586	[1]	$ 149,422	[1]	$ 91,813	[1]
Incentive income	0	[1]	1,320	[1]	2,317	[1]	6,368	[1]
Investment income	11,468	[1]	8,298	[1]	22,600	[1]	17,683	[1]
Total revenues	56,786		31,906		151,739		98,181
Expenses:
Compensation and benefits	(95,660)		(83,141)		(279,638)		(247,907)
Equity-based compensation	(7,320)		(7,498)		(20,877)		(27,482)
Incentive income compensation	(49,222)		(29,546)		(308,446)		(118,268)
General and administrative	(31,094)		(25,965)		(80,227)		(72,394)
Depreciation and amortization	(1,791)		(1,901)		(5,266)		(5,573)
Total expenses	(214,158)	[2]	(168,020)	[3]	(775,203)	[4]	(542,595)	[5]
Interest expense, net of interest income (1)	(17,337)	[6]	(10,789)	[6]	(42,931)	[6]	(33,639)	[6]
Other income (expense), net	148		(59)		412		8,534	[7]
Segment [Member]
Revenues:
Management fees	185,580	[1]	182,587	[1]	552,281	[1]	562,692	[1]
Incentive income	122,424	[1]	59,174	[1]	787,665	[1]	250,861	[1]
Investment income	53,558	[1]	62,801	[1]	170,184	[1]	150,382	[1]
Total revenues	361,562		304,562		1,510,130		963,935
Expenses:
Compensation and benefits	(95,561)		(83,080)		(279,344)		(247,787)
Equity-based compensation	(1,070)		(128)		(2,646)		(128)
Incentive income compensation	(49,222)		(29,546)		(308,446)		(118,268)
General and administrative	(27,389)		(24,429)		(80,889)		(73,665)
Depreciation and amortization	(1,791)		(1,901)		(5,266)		(5,573)
Total expenses	(175,033)	[2]	(139,084)	[3]	(676,591)	[4]	(445,421)	[5]
Adjusted net income before interest and other income (expense)	186,529		165,478		833,539		518,514
Interest expense, net of interest income (1)	(7,074)	[6],[8]	(7,687)	[6],[8]	(21,617)	[6],[8]	(23,914)	[6],[8]
Other income (expense), net	148		(59)		412		2,274	[7]
Adjusted net income	$ 179,603		$ 157,732		$ 812,334		$ 496,874

[1] The adjustment represents the elimination of amounts attributable to the consolidated funds.

[2] The expense adjustment consists of (a) equity-based compensation charges of $6,250 related to unit grants made before the Company’s initial public offering, (b) consolidated fund expenses of $32,604 and (c) expenses incurred by the Intermediate Holding Companies of $271.

[3] The expense adjustment consists of (a) equity-based compensation charges of $7,369 related to unit grants made before the Company’s initial public offering, (b) consolidated fund expenses of $21,452 and (c) expenses incurred by the Intermediate Holding Companies of $115.

[4] The expense adjustment consists of (a) equity-based compensation charges of $18,231 related to unit grants made before the Company’s initial public offering, (b) consolidated fund expenses of $79,434 and (c) expenses incurred by the Intermediate Holding Companies of $947.

[5] The expense adjustment consists of (a) equity-based compensation charges of $27,353 related to unit grants made before the Company’s initial public offering, (b) consolidated fund expenses of $69,428 and (c) expenses incurred by the Intermediate Holding Companies of $393.

[6] The interest expense adjustment represents the inclusion of interest expense attributable to non-controlling interests of the consolidated funds and the exclusion of segment interest income.

[7] The other income, net adjustment represents other income or expenses of OCG or its Intermediate Holding Companies. This amount is attributable to a reduction in the amount of the deferred tax asset under the tax receivable agreement associated with the 2007 Private Offering, which reduced the tax receivable agreement liability payable to OCGH unitholders.

[8] Interest income was $0.9 million and $0.8 million for the three months ended September 30, 2013 and 2012, respectively, and $2.4 million and $1.9 million for the nine months ended September 30, 2013 and 2012, respectively.