Fair Value Measurement - Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Loan servicing assets	$ 8,734	$ 6,831
Liabilities
Loan servicing liabilities	10,853	8,254
Fair Value, Inputs, Level 3
Assets
Loans	57,189	78,460
Notes receivable and residual certificates	16,033	19,074
Loan servicing assets	8,734	6,831
Total assets	81,956	104,365
Liabilities
Loan servicing liabilities	10,853	8,254
Trailing fee liabilities	1,775	1,276
Total liabilities	$ 12,628	$ 9,530

Trailing Fee Liabilities, Fair Value Disclosure

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value of financial and nonfinancial obligations.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Fair value of a liability representing servicing arrangements under which the estimated future revenue from contractually specified servicing fees, late charges, and other ancillary revenues are not expected to adequately compensate the servicer.

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