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Loans Held for Investment - By Region (Details) | Dec. 31, 2021 | Dec. 31, 2020
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Loans held for investment by Region [Line Items] |  |
Percentage of Loans concentrated in major states | 38.40% | 38.80%
New York |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 9.40% | 9.70%
California |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 9.60% | 9.60%
Pennsylvania |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 7.80% | 8.00%
New Jersey |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 6.00% | 6.20%
Texas |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 5.60% | 5.30%

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