COMMITMENTS AND CONTINGENCIES - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Unfunded Loan Commitments
Lease liabilities	$ 16,418
Operating lease, right-of-use asset	$ 14,700
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Other liabilities
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other assets
Operating expenses	$ 2,200	$ 1,100
Treasury bills traded and not yet settled	44,815	0	$ 0
Provision for loan losses
Unfunded Loan Commitments
Unfunded commitments of mortgage loan receivables held for investment	$ 204,000	$ 321,800
Length of additional mortgage loan financing	3 years
Unfunded commitments of mortgage loan receivables held for investment, additional funds	63.00%
U.S. Treasury Securities Traded, Not Yet Settled
Unfunded Loan Commitments
Treasury bills traded and not yet settled	$ 44,800

Debt Securities, Available-for-Sale, Not Yet Settled

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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