Certain Employee Benefit and Stock-Based Compensation Plans (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012 mo	Sep. 30, 2011	Sep. 30, 2012 mo	Sep. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense recognized related to all share-based payment arrangements			$ 84	$ 63
Maximum life of options (in years)			10 years
Shares exercisable at end of period	12,856,000		12,856,000
Weighted average exercisable price of shares exercisable at end of period	$ 90.81		$ 90.81
Treasury stock			1,700,000
Vesting period for restricted stock/unit awards, lower range	36		36
Vesting period for restricted stock/unit awards, upper range	60		60
Unrecognized deferred compensation expense related to nonvested share-based compensation arrangements	100		100
Cash-payable restricted share units outstanding	812,464		812,464
Total noninterest income	$ 1,689	$ 1,369	$ 4,227	$ 4,276