Fair Value Measurement - Schedule of Assets and Liabilities Measured at Fair Value (Details) - USD ($)	Sep. 30, 2024	Dec. 31, 2023
Assets
Loan servicing assets	$ 26,705,000	$ 28,092,000
Line of credit receivable	31,514,000	0
Total assets	858,279,000	1,246,322,000
Liabilities
Payable to securitization note holders	100,335,000	141,416,000
Trailing fee liabilities	4,300,000
Beneficial interest liabilities	13,162,000	4,221,000
Loan servicing liabilities	1,164,000	2,038,000
Fair Value, Inputs, Level 3
Assets
Loans	656,120,000	1,156,413,000
Beneficial interest assets	131,483,000	41,012,000
Loan servicing assets	26,705,000	28,092,000
Notes receivable and residual certificates	10,318,000	14,847,000
Line of credit receivable	31,514,000	0
Liabilities
Payable to securitization note holders	100,335,000	141,416,000
Trailing fee liabilities	4,345,000	4,251,000
Beneficial interest liabilities	13,162,000	4,221,000
Loan servicing liabilities	1,164,000	2,038,000
Total liabilities	119,006,000	151,926,000
Fair Value, Inputs, Level 2
Assets
Interest rate caps	$ 2,139,000	$ 5,958,000