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DEBT OBLIGATIONS AND CREDIT FACILITIES - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Oct. 01, 2019	Dec. 31, 2018	Jul. 31, 2017
Debt Instrument [Line Items]
Debt fair value			$ 4,127,994,000
Oaktree Capital Group Excluding Consolidated Funds
Debt Instrument [Line Items]
Debt obligations	$ 0		745,945,000
Total remaining principal	0		750,000,000
Debt issuance costs	0		4,055,000
Oaktree Capital Group Excluding Consolidated Funds \| Letter of Credit \| Credit Facility
Debt Instrument [Line Items]
Guarantee				$ 17,500,000
Oaktree Capital Group Excluding Consolidated Funds \| Level III
Debt Instrument [Line Items]
Debt fair value	0.0		$ 720,300,000
Average borrowing rate			4.40%
Consolidated Funds
Debt Instrument [Line Items]
Debt obligations	5,767,999,000		$ 4,127,994,000
Total remaining principal	5,826,362,000
Debt fair value	5,767,999,000
VIE consolidated assets	6,400,000,000		4,700,000,000
Consolidated Funds \| Senior notes
Debt Instrument [Line Items]
Debt fair value	$ 5,613,846,000		$ 3,976,602,000
Average borrowing rate	2.85%		2.69%
Consolidated Funds \| Revolving Credit Facility \| Credit Facility
Debt Instrument [Line Items]
Debt agreement term	10 years
Consolidated Funds \| Senior notes \| Credit Facility
Debt Instrument [Line Items]
Debt obligations	$ 158,477,000		$ 864,529,000
Total remaining principal	$ 159,411,000		870,098,000
Average borrowing rate	3.42%
Debt issuance costs	$ 934,000		5,569,000
Consolidated Funds \| Level III \| Credit Facility
Debt Instrument [Line Items]
Debt fair value	159,100,000		$ 871,300,000
Indirect Subsidiaries of Brookfield Asset Management, Inc.
Debt Instrument [Line Items]
Debt obligations		$ 746,300,000
Indirect Subsidiaries of Brookfield Asset Management, Inc. \| Consolidated Funds \| Senior notes \| Credit Facility
Debt Instrument [Line Items]
Total remaining principal		870,700,000
Debt issuance costs		$ 4,600,000
Indirect guarantee of debt obligations \| Oaktree Capital I
Debt Instrument [Line Items]
Guarantee	$ 750,000,000