DERIVATIVES AND HEDGING - Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative Assets:
Derivative assets	$ 560
Assets
Derivative Assets	221
Cash Collateral Received	0
Net Amount	339
Derivative Liabilities:
Derivative liabilities	(9,279)	$ (4,254)
Liabilities
Derivative Liabilities	(221)	0
Cash Collateral Pledged	0	0
Net Amount	(9,058)	(4,254)
Oaktree Capital Group Excluding Consolidated Funds \| Foreign-currency forward contracts
Derivative Assets:
Derivative assets	221
Assets
Derivative Assets	221
Cash Collateral Received	0
Net Amount	0
Derivative Liabilities:
Derivative liabilities	(8,733)	(1,703)
Liabilities
Derivative Liabilities	(221)	0
Cash Collateral Pledged	0	0
Net Amount	(8,512)	(1,703)
Consolidated Funds
Derivative Assets:
Derivative assets	339	6,890
Derivative Liabilities:
Derivative liabilities	(546)	(2,551)
Liabilities
Derivative Liabilities	0
Cash Collateral Pledged	0
Net Amount	(546)
Consolidated Funds \| Foreign-currency forward contracts
Derivative Assets:
Derivative assets	319	6,890
Assets
Derivative Assets	0	0
Cash Collateral Received	0	0
Net Amount	319	6,890
Derivative Liabilities:
Derivative liabilities	(375)	(2,551)
Liabilities
Derivative Liabilities	0	0
Cash Collateral Pledged	0	0
Net Amount	(375)	$ (2,551)
Consolidated Funds \| Options and futures
Derivative Assets:
Derivative assets	20
Assets
Derivative Assets	0
Cash Collateral Received	0
Net Amount	20
Derivative Liabilities:
Derivative liabilities	(12)
Liabilities
Derivative Liabilities	0
Cash Collateral Pledged	0
Net Amount	(12)
Consolidated Funds \| Total-return and interest-rate and credit default swaps
Derivative Liabilities:
Derivative liabilities	(159)
Liabilities
Derivative Liabilities	0
Cash Collateral Pledged	0
Net Amount	$ (159)

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