Loans TDR Modifications (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012 contracts		Jun. 30, 2011 contracts		Jun. 30, 2012 contracts		Jun. 30, 2011 contracts		Dec. 31, 2011
Financing Receivable, Modifications [Line Items]
Loans and Leases Receivable, Impaired, Commitment to Lend	$ 4				$ 4				$ 5
Financing Receivable, Restructured During Period, Number Of Contracts	2,077		767		3,355		1,557
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	7	[1]	26	[2]	14	[1]	76	[2]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	64	[3]	119	[4]	120	[3]	254	[4]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	50		44		76		75
total modifications	121		189		210		405
PrincipalForgivenessRestructuringImpact	1		8		1		9
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	147	[5]	174	[6]	327	[7]	515	[8]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	17	[5]	44	[6]	36	[7]	118	[8]
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	80		56		183		78
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	0	[1]	19	[2]	0	[1]	27	[2]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	1	[3]	22	[4]	2	[3]	22	[4]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	3		3		15		8
total modifications	4		44		17		57
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	14	[5]	10	[6]	25	[7]	20	[8]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	1	[5]	0	[6]	3	[7]	2	[8]
Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	13		9		23		25
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	6	[1]	4	[2]	12	[1]	22	[2]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	6	[3]	0	[4]	7	[3]	16	[4]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	0		3		2		15
total modifications	12		7		21		53
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	0	[5]	2	[6]	4	[7]	6	[8]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	0	[5]	1	[6]	4	[7]	1	[8]
Commercial Portfolio Segment [Member] | Commercial Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	5		8		12		82
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	1	[1]	3	[2]	2	[1]	27	[2]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	0	[3]	0	[4]	0	[3]	2	[4]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	10		31		11		41
total modifications	11		34		13		70
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	4	[5]	8	[6]	7	[7]	14	[8]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	4	[5]	15	[6]	6	[7]	24	[8]
Residential Portfolio Segment [Member] | Residential Nonguaranteed [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	199		258		424		528
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	0	[1]	0	[2]	0	[1]	0	[2]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	21	[3]	61	[4]	41	[3]	142	[4]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	0		5		1		8
total modifications	21		66		42		150
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	28	[5]	94	[6]	56	[7]	334	[8]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	9	[5]	23	[6]	14	[7]	75	[8]
Residential Portfolio Segment [Member] | Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	457		398		841		743
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	0	[1]	0	[2]	0	[1]	0	[2]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	33	[3]	31	[4]	64	[3]	62	[4]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	2		0		3		0
total modifications	35		31		67		62
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	38	[5]	47	[6]	81	[7]	111	[8]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	3	[5]	4	[6]	6	[7]	11	[8]
Residential Portfolio Segment [Member] | Residential Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	140		27		175		50
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	0	[1]	0	[2]	0	[1]	0	[2]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	1	[3]	5	[4]	1	[3]	10	[4]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	20		1		29		1
total modifications	21		6		30		11
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	6	[5]	8	[6]	17	[7]	23	[8]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	0	[5]	1	[6]	2	[7]	5	[8]
Consumer Portfolio Segment [Member] | Consumer Indirect
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	795				795
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	0	[1]			0	[1]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	0	[3]			0	[3]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	14				14
total modifications	14				14
Consumer Portfolio Segment [Member] | Consumer Other Direct [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	27		11		39		51
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	0	[1]	0	[2]	0	[1]	0	[2]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	0	[3]	0	[4]	0	[3]	0	[4]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	1		1		1		2
total modifications	1		1		1		2
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	0	[5]	5	[6]	2	[7]	7	[8]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	0	[5]	0	[6]	0	[7]	0	[8]
Consumer Portfolio Segment [Member] | Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Restructured During Period, Number Of Contracts	361				863
Financing Receivable, Amount Restructured During Period, Principal Forgiveness Granted	0	[1]			0	[1]
Financing Receivable, Amount Restructured During Period, Other Concessions Granted	2	[3]			5	[3]
Financing Receivable, Amount Restructured During Period, Term Extension and/or Other Concessions Granted	0				0
total modifications	2				5
Financing Receivable, Restructured, Payment Default During Peiriod, Number of Contracts	57	[5]			135	[7]
Financing Receivable, Restructured, Payment Default During Period, Amortized Cost at Default	$ 0	[5]			$ 1	[7]

[1] Restructured loans which had forgiveness of amounts contractually due under the terms of the loan typically have had multiple concessions including rate modifications and/or term extensions. The total amount of charge-offs associated with principal forgiveness was $1 million during both the three and six months ended June 30, 2012.

[2] Restructured loans which had forgiveness of amounts contractually due under the terms of the loan typically have had multiple concessions including rate modifications and/or term extensions. The total amount of charge-offs associated with principal forgiveness during the three and six months ended June 30, 2011 was $8 million and $9 million, respectively.

[3] Restructured loans which had a modification of the loan's contractual interest rate may also have had an extension of the loan's contractual maturity date and/or other concessions. The financial effect of modifying the interest rate on the loans modified as a TDR was immaterial to the financial statements during the three and six months ended June 30, 2012.

[4] Restructured loans which had a modification of the loan's contractual interest rate may also have had an extension of the loan's contractual maturity date and/or other concessions. The financial effect of modifying the interest rate on the loans modified as a TDR was immaterial to the financial statements during the three and six months ended June 30, 2011.

[5] For the three months ended June 30, 2012, this represents defaults on loans that were first modified between the periods April 1, 2011 and June 30, 2012.

[6] For the three months ended June 30, 2011, this represents defaults on loans that were first modified between the periods April 1, 2010 and June 30, 2011.

[7] For the six months ended June 30, 2012, this represents defaults on loans that were first modified between the periods January 1, 2011 and June 30, 2012.

[8] For the six months ended June 30, 2011, this represents defaults on loans that were first modified between the periods January 1, 2010 and June 30, 2011.