RELATED PARTY TRANSACTIONS - Related Party Costs Incurred (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Related Party Transaction [Line Items]
Payable	$ 4,562		$ 4,562		$ 4,156
ACREM | Continuing Operations
Related Party Transaction [Line Items]
Incurred	4,572	$ 3,732	8,411	$ 7,051
Payable	4,562		4,562		4,156
ACREM | Continuing Operations | Management fees
Related Party Transaction [Line Items]
Incurred	2,801	2,258	5,417	4,167
Payable	2,801		2,801		2,613
ACREM | Continuing Operations | Incentive fees
Related Party Transaction [Line Items]
Incurred	965	693	1,323	1,351
Payable	965		965		830
ACREM | Continuing Operations | General and administrative expenses
Related Party Transaction [Line Items]
Incurred	796	788	1,631	1,540
Payable	796		796		703
ACREM | Continuing Operations | Direct costs
Related Party Transaction [Line Items]
Incurred	10	$ (7)	40	$ (7)
Payable	$ 0		$ 0		$ 10