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Fair Value Measurement - Additional Information (Details) - Non-Recoverable Rate - Level 3 - Appraisal value | Mar. 31, 2021 | Dec. 31, 2020
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Minimum |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held for investment, measurement input | 0.00% | 0.00%
Maximum |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held for investment, measurement input | 89.00% | 89.00%
Weighted average |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held for investment, measurement input | 27.00% | 14.00%

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