Other Operating Expenses (Schedule Of Other Operating Expenses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Operating Expenses [Abstract]
Insurance Commissions	$ 106	$ 99	$ 309	$ 290
Communications and Information Technology	72	70	212	203
Lease And Loan Administration	41	34	116	100
Marketing and Advertising Expense	33	27	96	75
Vehicle remarketing and repossession	29	24	82	70
Federal Deposit Insurance Corporation Premium Expense	27	26	82	68
Professional Fees	28	25	81	75
Depreciation, Nonproduction	22	19	67	61
Occupancy, Net	11	13	34	38
Taxes, Miscellaneous	6	10	22	27
Other Cost and Expense, Operating	49	71	148	182
Other Noninterest Expense	$ 424	$ 418	$ 1,249	$ 1,189