RELATED PARTY TRANSACTIONS AND INTERESTS IN CONSOLIDATED ENTITIES - Sub-Allocation Fee Schedule (Details)	9 Months Ended
	Sep. 30, 2020
Related Party Transaction [Line Items]
Sub-allocation fees, maximum percentage of assets	10.00%
Core Assets
Related Party Transaction [Line Items]
Sub-Allocation Fees	0.065%
Core Plus Assets
Related Party Transaction [Line Items]
Sub-Allocation Fees	0.13%
Yield Assets
Related Party Transaction [Line Items]
Sub-Allocation Fees	0.375%
High Alpha Assets
Related Party Transaction [Line Items]
Sub-Allocation Fees	0.70%
Cash, Treasuries, Equities and Alternatives
Related Party Transaction [Line Items]
Sub-Allocation Fees	0.00%
Cash, Treasuries, Equities and Alternatives | Minimum
Related Party Transaction [Line Items]
Performance revenue, percentages	0.00%
Cash, Treasuries, Equities and Alternatives | Maximum
Related Party Transaction [Line Items]
Performance revenue, percentages	20.00%