Summary of Significant Accounting Policies - Schedule of Impact of Adoption (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Jan. 01, 2021	Dec. 31, 2020
Assets
Loans receivable held-for-investment	$ 6,407,305	$ 64,274	$ 6,131,825
Interests in loans receivable held-for-investment		406
Accrued interest receivable, net	25,990	357	35,668
Liabilities
Unfunded loan commitments		13,214
Total impact of ASU 2016-13 adoption on retained earnings	$ 664,700	$ 78,251	$ 526,205

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