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Loans Held for Investment - by Region (Details) | Dec. 31, 2016 | Dec. 31, 2015
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Loans held for investment by Region [Line Items] |  |
Percentage of Loans concentrated in major states | 40.30% | 39.80%
New York |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 10.30% | 10.10%
California |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 9.40% | 9.60%
Pennsylvania |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 8.40% | 8.10%
New Jersey |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 6.90% | 6.70%
Illinois |  |
Loans held for investment by Region [Line Items] |  |
Percentage of Loans held in state | 5.30% | 5.30%

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