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VARIABLE INTEREST ENTITIES - Narrative (Details) $ in Thousands		3 Months Ended					6 Months Ended	12 Months Ended
	Jan. 28, 2021 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan	Jan. 11, 2019 USD ($)	Mar. 31, 2017 USD ($)
Variable Interest Entity [Line Items]
Financing receivable, unpaid principal balance		$ 62,900		$ 105,400			$ 62,900	$ 105,400
Loans held for investment		2,605,893		2,414,383			2,605,893	$ 2,414,383
Sale of common stock		103,393	$ 2,874	2,119	$ 101,790	$ 100,870
Credit risk, financial instrument, maximum exposure							238,200
ACRE Commercial Mortgage 2021-FL4 Ltd. and ACRE Commercial Mortgage 2021-FL4 LLC \| Preferred Stock
Variable Interest Entity [Line Items]
Sale of common stock	$ 64,300
ACRE Commercial Mortgage 2021-FL4 Ltd. and ACRE Commercial Mortgage 2021-FL4 LLC \| Preferred Stock \| Wholly Owned Subsidiary To Parent Company
Variable Interest Entity [Line Items]
Sale of common stock							$ 64,300
Floating Rate Notes, Weighted Average Coupon Rate, LIBOR Plus 1.85%
Variable Interest Entity [Line Items]
Number of properties collateralized for mortgage loan \| loan							18	16
Receivables related to repayments of outstanding principal		494,100		451,600			$ 494,100	$ 451,600
Mortgaged Assets \| Holdco
Variable Interest Entity [Line Items]
Principal amount of certificates retained by wholly owned subsidiary of the entity		58,500					58,500
Offered Certificates \| Parent Company
Variable Interest Entity [Line Items]
Preferred equity fully funded amount		52,900					52,900
Secured funding agreements \| Parent Company
Variable Interest Entity [Line Items]
Loans held for investment		111,400					111,400
Secured, Floating Rate Notes \| ACRE Commercial Mortgage 2021-FL4 Ltd. and ACRE Commercial Mortgage 2021-FL4 LLC
Variable Interest Entity [Line Items]
Aggregate principal amount	$ 603,000
Secured, Floating Rate Notes \| ACRE Commercial Mortgage 2021-FL4 Ltd. and ACRE Commercial Mortgage 2021-FL4 LLC \| Wholly Owned Subsidiary To Parent Company
Variable Interest Entity [Line Items]
Aggregate principal amount		62,500					62,500
Collateral amount		126,800					$ 126,800
Repayments of debt		11,000
FL4 Mortgage Assets
Variable Interest Entity [Line Items]
Number of properties collateralized for mortgage loan \| loan							17	17
Receivables related to repayments of outstanding principal		532,700		522,800			$ 532,700	$ 522,800
Financing Receivable, Excluding Accrued Interest, Receivables Related to Repayments of Outstanding Principal on Mortgage Assets		$ 2,300		$ 23,200			$ 2,300	$ 23,200
Wells Fargo Facility \| Notes Payable
Variable Interest Entity [Line Items]
Debt commitment										$ 308,800
Wells Fargo Facility \| Notes Payable \| 2019 FL3 CLO Securitization
Variable Interest Entity [Line Items]
Debt commitment									$ 504,100
Wells Fargo Facility \| Collateralized Loan Obligations
Variable Interest Entity [Line Items]
Debt commitment										$ 32,400
Wells Fargo Facility \| Collateralized Loan Obligations \| 2019 FL3 CLO Securitization
Variable Interest Entity [Line Items]
Debt commitment									$ 52,900