Description Of Business (Percentage Of Consumer Loans Assigned Based On Unit and Dollar Volumes) (Details)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Portfolio Program [Member]
Description Of Business [Line Items]
Percentage of new consumer loans in unit volume		67.20%	69.70%	72.50%
Percentage of new consumer loans in dollar volume	[1]	64.30%	67.20%	68.50%
Purchase Program [Member]
Description Of Business [Line Items]
Percentage of new consumer loans in unit volume		32.80%	30.30%	27.50%
Percentage of new consumer loans in dollar volume	[1]	35.70%	32.80%	31.50%

[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.