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Description Of Business (Percentage Of Consumer Loans Assigned Based On Unit and Dollar Volumes) (Details) | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Portfolio Program [Member] |  |  |
Description Of Business [Line Items] |  |  |
Percentage of new consumer loans in unit volume | 78.60% | 87.40% | 90.70%
Percentage of new consumer loans in dollar volume | 71.40% | 82.80% | 87.80%
Purchase Program [Member] |  |  |
Description Of Business [Line Items] |  |  |
Percentage of new consumer loans in unit volume | 21.40% | 12.60% | 9.30%
Percentage of new consumer loans in dollar volume | 28.60% | 17.20% | 12.20%

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