Goodwill and Other Intangible Assets - Mortgage Servicing Rights (Details 3) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Mortgage servicing rights activity
Fair value at the beginning of the period	$ 7,614,000,000	$ 7,223,000,000
MSR activity
Originations of MSRs	690,000,000	572,000,000
Purchase of MSRs	(6,000,000)	1,000,000
Disposition of MSRs	(399,000,000)	0
Changes in fair value due to modeled amortization	(259,000,000)	(353,000,000)
Net additions and amortization	26,000,000	220,000,000
Changes due to market interest rates	546,000,000	644,000,000
Other changes in valuation due to inputs and assumptions	(237,000,000)	(48,000,000)
Total change in fair value of MSRs	309,000,000	596,000,000
Fair value at March 31	7,949,000,000	8,039,000,000
Change in unrealized gains/(losses) included in income related to MSRs held at March 31	309,000,000	596,000,000
Contractual service fees, late fees and other ancillary fees included in income	869,000,000	1,033,000,000
Third-party mortgage loans serviced at March 31 (in billions)	856,000,000,000	892,000,000,000
Servicer advances at March 31, (in billions)	10,500,000,000	11,200,000,000
MSR activity supplemental information
Commercial Real Estate, Fair Value, Period Increase (Decrease)	(2,000,000)	(2,000,000)
Commercial Real Estate, Fair Value	$ 21,000,000	$ 29,000,000