Loans Troubled Debt Restructurings (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 contracts	Dec. 31, 2012 contracts	Dec. 31, 2011 contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	975	683	1,238
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	$ 48	$ 52	$ 204
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	55	84	71
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	5	5	14
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	5	9	14
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	3	5	22
Commercial Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	1	10	32
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	0	7	28
Residential Nonguaranteed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	287	141	455
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	23	20	108
Home Equity Line of Credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	188	164	220
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	10	11	22
Residential Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	48	24	33
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	3	3	7
Consumer Other Direct [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	15	4	10
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	1	0	0
Consumer Indirect [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	207	43
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	2
Consumer Credit Card Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	169	204	403
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	$ 1	$ 1	$ 3