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Loans Held for Investment - By Region (Details) | Dec. 31, 2019 | Dec. 31, 2018
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Loans held for investment by Region [Line Items] |  |
Percentage of Loans concentrated in major states | 39.40% | 39.90%
New York |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 10.10% | 10.30%
California |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 9.40% | 9.30%
Pennsylvania |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 8.40% | 8.50%
New Jersey |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 6.60% | 6.80%
Texas |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 4.90% |
Illinois |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state |  | 5.00%

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