Accumulated Other Comprehensive Loss (Schedule Of Accumulated Other Comprehensive Loss) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Investment securities, Balance at beginning of period, net of tax	$ (68)	$ 150
Investment securities, Net unrealized holding gains (losses) arising during the period	116	(242)
Investment securities, Provision (benefit) for income taxes	41	(89)
Investment securities, Net unrealized holding gains (losses) arising during period, net of tax	75	(153)
Investment securities, Net realized gains included in net securities gains	1	0
Investment securities, Provision for income taxes	0	0
Investment securities, Reclassification adjustment for net securities gains included in net income, net of tax	1	0
Investment securities, Change in net unrealized (losses) gains on investment securities available-for-sale, net of tax	74	(153)
Investment securities, Balance at end of period, net of tax	6	(3)
Benefit plans, Balance at beginning of period, net of tax	(323)	(563)
Less: Amortization of actuarial net loss	18	44
Less: Amortization of prior service cost	1	1
Benefit plans, Amounts recognized in salaries and benefits expense	19	45
Benefit plans, Provision for income taxes	6	17
Benefit plans, Change in defined benefit pension and other postretirement plans adjustment, net of tax	13	28
Benefit plans, Balance at end of period, net of tax	(310)	(535)
Total accumulated other comprehensive loss at end of period, net of tax	$ (304)	$ (538)	$ (391)