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Description of Business (Percentage of Consumer Loans Assigned Based on Unit Volumes) (Details) | 3 Months Ended
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Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013
Portfolio Program [Member] |  |  |  |  |  |  |
Description Of Business [Line Items] |  |  |  |  |  |  |
Percentage of new consumer loans | 90.50% | 91.40% | 91.70% | 92.40% | 92.90% | 93.90% | 94.40%
Purchase Program [Member] |  |  |  |  |  |  |
Description Of Business [Line Items] |  |  |  |  |  |  |
Percentage of new consumer loans | 9.50% | 8.60% | 8.30% | 7.60% | 7.10% | 6.10% | 5.60%

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- Definition Percentage Of New Consumer Loan Assignments + References No definition available. + Details
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