BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Jan. 01, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unamortized retained loan discounts	$ 8,800		$ 9,000
Loan receivable, nonaccrual, past due period (more than)	60 days
Cumulative-effective adjustment	$ 378,682		362,033	$ 377,460	$ 373,549
Allowance for credit losses	1,940		1,106
Distributions in Excess of Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effective adjustment	$ (853,108)		(837,846)	$ (806,923)	$ (804,227)
Cumulative-effect adjustment upon adoption of ASU 2016-13 (Note 2)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effective adjustment			(619)
Allowance for credit losses			783
Cumulative-effect adjustment upon adoption of ASU 2016-13 (Note 2) | Distributions in Excess of Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effective adjustment			$ (619)
CECL reserve transition gross		$ (783)
CECL reserve transition, deferred tax asset		$ 164