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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, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Portfolio Program [Member] |  |  |  |
Description Of Business [Line Items] |  |  |  |
Percentage of new consumer loans in unit volume |  | 69.70% | 72.50% | 78.60%
Percentage of new consumer loans in dollar volume | [1] | 67.20% | 68.50% | 71.40%
Purchase Program [Member] |  |  |  |
Description Of Business [Line Items] |  |  |  |
Percentage of new consumer loans in unit volume |  | 30.30% | 27.50% | 21.40%
Percentage of new consumer loans in dollar volume | [1] | 32.80% | 31.50% | 28.60%
[1] | Represents advances paid to Dealers on Consumer Loans assigned under our Portfolio Program and one-time payments made to Dealers to purchase Consumer Loans assigned under our Purchase Program. Payments of Dealer Holdback (as defined below) and accelerated Dealer Holdback are not included.

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