UNITHOLDERS' CAPITAL - Summary of Net Income (Loss) (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Weighted average Oaktree Operating Group units outstanding (in thousands):
Units outstanding (in shares)									80,045	70,526	64,148
Oaktree Operating Group net income:
Net income	$ 102,308	$ (20,898)	$ 121,528	$ 184,400	$ 118,296	$ 143,091	$ 65,757	$ 137,401	$ 387,338	$ 464,545	$ 689,482
Net income attributable to OCG Class A unitholders:
Oaktree Operating Group net income attributable to OCG Class A unitholders									137,921	228,791	295,161
Non-Operating Group income (expense)									(8,662)	(632)	144,143
Income tax expense of Intermediate Holding Companies									(1,736)	(17,018)	(207,810)
Net income attributable to Oaktree Capital Group, LLC Class A unitholders									$ 127,523	$ 211,141	$ 231,494
Oaktree Operating Group
Weighted average Oaktree Operating Group units outstanding (in thousands):
Units outstanding (in shares)									159,129	156,916	155,791
Oaktree Operating Group net income:
Net income									$ 302,337	$ 521,227	$ 717,283
Net income attributable to OCG Class A unitholders:
OCGH non-controlling interest									1,779	2,659	2,662
Series A Preferred Units | Oaktree Operating Group
Oaktree Operating Group net income:
Net income									$ 27,316	$ 12,277	$ 0
OCGH Units | Oaktree Operating Group
Weighted average Oaktree Operating Group units outstanding (in thousands):
Units outstanding (in shares)									79,084	86,390	91,643
Oaktree Operating Group net income:
Net income									$ 137,100	$ 280,159	$ 422,122
Class A Units | Oaktree Operating Group
Weighted average Oaktree Operating Group units outstanding (in thousands):
Units outstanding (in shares)									80,045	70,526	64,148
Oaktree Operating Group net income:
Net income									$ 137,921	$ 228,791	$ 295,161