UNITHOLDERS' CAPITAL - Summary of Net Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Weighted average Oaktree Operating Group units outstanding (in thousands):
Weighted average Oaktree Operating Group units outstanding (in shares)	74,340,000	71,177,000	72,994,000	69,556,000
Oaktree Operating Group net income:
Oaktree Operating Group net income	$ 121,528	$ 65,757	$ 305,928	$ 203,158
Net income attributable to OCG Class A unitholders:
Oaktree Operating Group net income attributable to OCG Class A unitholders	43,068	34,177	97,934	90,539
Non-Operating Group income (expense)	(676)	(328)	(4,320)	(308)
Income tax benefit (expense) of Intermediate Holding Companies	52	(2,728)	(3,916)	(6,378)
Net income attributable to OCG Class A unitholders	$ 42,444	$ 31,121	$ 89,698	$ 83,853
Oaktree Operating Group
Weighted average Oaktree Operating Group units outstanding (in thousands):
Weighted average Oaktree Operating Group units outstanding (in shares)	159,609,000	157,184,000	158,365,000	156,689,000
Oaktree Operating Group net income:
Oaktree Operating Group net income	$ 99,294	$ 75,473	$ 226,461	$ 205,090
Net income attributable to OCG Class A unitholders:
OCGH non-controlling interest	$ 618	$ 697	$ 1,261	$ 1,389
Weighted average Oaktree Operating Group units outstanding (in shares) | Oaktree Operating Group
Weighted average Oaktree Operating Group units outstanding (in thousands):
Weighted average Oaktree Operating Group units outstanding (in shares)	85,269,000	86,007,000	85,371,000	87,133,000
Oaktree Operating Group net income:
Oaktree Operating Group net income	$ 49,397	$ 41,296	$ 114,869	$ 114,551
Series A Preferred Units | Oaktree Operating Group
Oaktree Operating Group net income:
Oaktree Operating Group net income	$ 6,829	$ 0	$ 13,658	$ 0
Class A Units | Oaktree Operating Group
Weighted average Oaktree Operating Group units outstanding (in thousands):
Weighted average Oaktree Operating Group units outstanding (in shares)	74,340,000	71,177,000	72,994,000	69,556,000
Oaktree Operating Group net income:
Oaktree Operating Group net income	$ 43,068	$ 34,177	$ 97,934	$ 90,539