RELATED PARTY TRANSACTIONS - Related Party Costs Incurred (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Related Party Transaction [Line Items]
Incurred	$ 358	$ 658
Payable	3,823		$ 4,156
ACREM \| Continuing Operations
Related Party Transaction [Line Items]
Incurred	3,837	3,319
Payable	3,823		4,156
ACREM \| Continuing Operations \| Management fees
Related Party Transaction [Line Items]
Incurred	2,616	1,909
Payable	2,616		2,613
ACREM \| Continuing Operations \| Incentive fees
Related Party Transaction [Line Items]
Incurred	358	658
Payable	358		830
ACREM \| Continuing Operations \| General and administrative expenses
Related Party Transaction [Line Items]
Incurred	834	752
Payable	834		703
ACREM \| Continuing Operations \| Direct costs
Related Party Transaction [Line Items]
Incurred	29	$ 0
Payable	$ 15		$ 10

Carrying amount as of the balance sheet date of obligations due all related parties.

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+ Details