QUARTERLY FINANCIAL DATA (Details) - USD ($) $ / shares in Units, $ 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
Quarterly Financial Data [Abstract]
Revenues	$ 143,899	$ 205,190	$ 313,483	$ 266,415	$ 594,248	$ 241,227	$ 213,283	$ 337,321
Expenses	(93,689)	(245,480)	(265,888)	(237,474)	(373,762)	(191,167)	(184,606)	(251,036)	$ (842,531)	$ (1,000,571)	$ (1,025,343)
Other income	50,570	24,190	75,785	159,957	(95,243)	99,599	41,947	57,513	310,502	103,816	460,500
Income before income taxes	100,780	(16,100)	123,380	188,898	125,243	149,659	70,624	143,798	396,958	489,324	904,924
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 Oaktree Capital Group, LLC	$ 54,473	$ (16,648)	$ 42,444	$ 47,254	$ 74,538	$ 52,750	$ 31,121	$ 52,732	$ 154,839	$ 223,418	$ 231,494
Net income per unit (basic and diluted):
Net income per Class A unit (in dollars per share)	$ 0.56	$ (0.22)	$ 0.57	$ 0.66	$ 1.04	$ 0.74	$ 0.44	$ 0.78	$ 1.59	$ 2.99	$ 3.61
Distributions declared per Class A unit (in dollars per share)	$ 0.03	$ 3.13	$ 1.05	$ 0.75	$ 0.70	$ 0.55	$ 0.96	$ 0.76	$ 4.96	$ 2.97	$ 3.21