Asset Quality (Home Equity and Residential Real Estate Balances) (Details) (USD $)	Sep. 30, 2014		Dec. 31, 2013		Sep. 30, 2013
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 200,872,000,000	[1],[2]	$ 195,613,000,000	[1],[2]	$ 192,856,000,000
Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding Purchased Impaired Loans	43,382,000,000		44,376,000,000
Purchased Impaired Loans - Outstanding Balance	4,795,000,000		5,548,000,000
Government insured or guaranteed residential real estate mortgages	1,262,000,000		1,704,000,000
Purchase accounting adjustments - purchased impaired loans	(33,000,000)		(116,000,000)
Total loans	$ 49,406,000,000		$ 51,512,000,000

[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.