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Fair Value Measurement - Additional Information (Detail) - Non-Recoverable Rate - Level 3 - Appraisal value | Mar. 31, 2020 | Dec. 31, 2019
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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 | 15.00% | 50.00%
Weighted average |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans held for investment, measurement input | 3.00% | 6.00%

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