Loan Sale and Servicing Activities and Variable Interest Entities (Consolidated VIEs - Carrying Value) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash and due from banks	$ 4,360,000,000	[1]	$ 4,043,000,000	[1]	$ 4,043,000,000	$ 4,043,000,000	$ 5,220,000,000	$ 4,105,000,000
Interest-earning deposits with banks	31,779,000,000	[1]	12,135,000,000	[1]
Loans	204,817,000,000	[1],[2]	195,613,000,000	[1],[2]			185,856,000,000
Allowance for loan and lease losses	(3,331,000,000)	[1]	(3,609,000,000)	[1]			(4,036,000,000)	(4,347,000,000)
Equity investments	10,728,000,000	[1],[3]	10,560,000,000	[1],[3]
Other assets	23,482,000,000	[1],[2]	22,552,000,000	[1],[2]
Total assets	345,072,000,000		320,192,000,000
Other borrowed funds	3,357,000,000	[1],[2]	3,060,000,000	[1],[2]
Accrued expenses	5,187,000,000	[1],[3]	4,690,000,000	[1],[3]
Other liabilities	4,550,000,000	[1]	4,187,000,000	[1]
Total liabilities	298,998,000,000		276,155,000,000
Variable Interest Entity, Primary Beneficiary [Member]
Cash and due from banks	6,000,000	[1]	5,000,000	[1]
Interest-earning deposits with banks	6,000,000	[1]	7,000,000	[1]
Loans	1,606,000,000	[1]	1,736,000,000	[1]
Allowance for loan and lease losses	(50,000,000)	[1]	(58,000,000)	[1]
Equity investments	492,000,000	[1]	582,000,000	[1]
Other assets	483,000,000	[1]	591,000,000	[1]
Total assets	2,543,000,000		2,863,000,000
Other borrowed funds	347,000,000	[1]	414,000,000	[1]
Accrued expenses	70,000,000	[1]	83,000,000	[1]
Other liabilities	206,000,000	[1]	252,000,000	[1]
Total liabilities	623,000,000		749,000,000
Variable Interest Entity, Primary Beneficiary [Member] | Credit Card and Other Securitization Trusts [Member]
Loans	1,606,000,000		1,736,000,000
Allowance for loan and lease losses	(50,000,000)		(58,000,000)
Other assets	31,000,000		25,000,000
Total assets	1,587,000,000		1,703,000,000
Other borrowed funds	166,000,000		184,000,000
Total liabilities	166,000,000		184,000,000
Variable Interest Entity, Primary Beneficiary [Member] | Tax Credit Investments
Cash and due from banks	6,000,000		5,000,000
Interest-earning deposits with banks	6,000,000		7,000,000
Equity investments	492,000,000		582,000,000
Other assets	452,000,000		566,000,000
Total assets	956,000,000		1,160,000,000
Other borrowed funds	181,000,000		230,000,000
Accrued expenses	70,000,000		83,000,000
Other liabilities	206,000,000		252,000,000
Total liabilities	$ 457,000,000		$ 565,000,000

[1] Amounts represent the assets or liabilities of consolidated variable interest entities (VIEs).

[2] Amounts represent items for which we have elected the fair value option.

[3] Amounts for 2013 period have been updated to reflect the first quarter 2014 adoption of ASU 2014-01 related to investments in low income housing tax credits.