SUBSEQUENT EVENTS (Details) - USD ($) $ in Thousands		1 Months Ended
		Oct. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	[2]
Subsequent Event [Line Items]
Face value of financing receivable	[1]		$ 3,580,521	$ 3,083,821
Subsequent Event
Subsequent Event [Line Items]
Committed capital		$ 371,400
Subsequent Event | OBX 2021-J1 Trust | Consolidated VIEs | Residential Mortgage Loans
Subsequent Event [Line Items]
Face value of financing receivable		453,600
Subsequent Event | OBX 2021-INV2 | Consolidated VIEs | Residential Mortgage Loans
Subsequent Event [Line Items]
Face value of financing receivable		$ 343,600

[1] (4)Includes $3.7 million and $47.0 million of residential mortgage loans held for sale at September 30, 2021 and December 31, 2020, respectively, and $2.1 million and $0 of corporate loans held for sale at September 30, 2021 and December 31, 2020, respectively.

[2] (1)Derived from the audited consolidated financial statements at December 31, 2020.