Description Of Business (Percentage Of Consumer Loans Assigned Based On Unit and Dollar Volumes) (Details)		12 Months Ended
		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.