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Description of Business (Percentage of Consumer Loans Assigned Based on Unit Volumes) (Details) | 3 Months Ended
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Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014
Portfolio Program [Member] |  |  |  |  |  |
Description Of Business [Line Items] |  |  |  |  |  |
Percentage of new consumer loans | 87.70% | 88.60% | 89.00% | 90.50% | 91.40% | 91.70%
Purchase Program [Member] |  |  |  |  |  |
Description Of Business [Line Items] |  |  |  |  |  |
Percentage of new consumer loans | 12.30% | 11.40% | 11.00% | 9.50% | 8.60% | 8.30%

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- Details
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