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Loans Held for Investment - By Region (Details) | Dec. 31, 2020 | Dec. 31, 2019
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Loans held for investment by Region [Line Items] |  |
Percentage of Loans concentrated in major states | 38.80% | 39.40%
New York |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 9.70% | 10.10%
California |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 9.60% | 9.40%
Pennsylvania |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 8.00% | 8.40%
New Jersey |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 6.20% | 6.60%
Texas |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 5.30% | 4.90%

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