Allowance for Credit Losses (Schedule of Information Regarding Impaired Loans) (Details) (USD $) In Millions				9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended				9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended			9 Months Ended				9 Months Ended				9 Months Ended
	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Sep. 30, 2011 With A Related Allowance Recorded [Member] Commercial and Industrial [Member]	Dec. 31, 2010 With A Related Allowance Recorded [Member] Commercial and Industrial [Member]	Sep. 30, 2011 With A Related Allowance Recorded [Member] Commercial Real Estate - Other [Member]	Dec. 31, 2010 With A Related Allowance Recorded [Member] Commercial Real Estate - Other [Member]	Sep. 30, 2011 With A Related Allowance Recorded [Member] Commercial Real Estate - Residential ADC [Member]	Dec. 31, 2010 With A Related Allowance Recorded [Member] Commercial Real Estate - Residential ADC [Member]	Sep. 30, 2011 With A Related Allowance Recorded [Member] Commercial Specialized Lending [Member]	Dec. 31, 2010 With A Related Allowance Recorded [Member] Commercial Specialized Lending [Member]	Sep. 30, 2011 With A Related Allowance Recorded [Member] Direct Retail Lending [Member]	Dec. 31, 2010 With A Related Allowance Recorded [Member] Direct Retail Lending [Member]	Sep. 30, 2011 With A Related Allowance Recorded [Member] Retail Revolving Credit [Member]	Dec. 31, 2010 With A Related Allowance Recorded [Member] Retail Revolving Credit [Member]	Sep. 30, 2011 With A Related Allowance Recorded [Member] Retail Residential Mortgage [Member]		Dec. 31, 2010 With A Related Allowance Recorded [Member] Retail Residential Mortgage [Member]		Sep. 30, 2011 With A Related Allowance Recorded [Member] Retail Sales Finance [Member]	Dec. 31, 2010 With A Related Allowance Recorded [Member] Retail Sales Finance [Member]	Sep. 30, 2011 With A Related Allowance Recorded [Member] Retail Specialized Lending [Member]	Dec. 31, 2010 With A Related Allowance Recorded [Member] Retail Specialized Lending [Member]	Sep. 30, 2011 With No Related Allowance Recorded [Member] Commercial and Industrial [Member]	Dec. 31, 2010 With No Related Allowance Recorded [Member] Commercial and Industrial [Member]	Sep. 30, 2011 With No Related Allowance Recorded [Member] Commercial Real Estate - Other [Member]	Dec. 31, 2010 With No Related Allowance Recorded [Member] Commercial Real Estate - Other [Member]	Sep. 30, 2011 With No Related Allowance Recorded [Member] Commercial Real Estate - Residential ADC [Member]	Dec. 31, 2010 With No Related Allowance Recorded [Member] Commercial Real Estate - Residential ADC [Member]	Sep. 30, 2011 With No Related Allowance Recorded [Member] Commercial Specialized Lending [Member]	Sep. 30, 2011 With No Related Allowance Recorded [Member] Direct Retail Lending [Member]	Dec. 31, 2010 With No Related Allowance Recorded [Member] Direct Retail Lending [Member]	Sep. 30, 2011 With No Related Allowance Recorded [Member] Retail Residential Mortgage [Member]		Dec. 31, 2010 With No Related Allowance Recorded [Member] Retail Residential Mortgage [Member]		Sep. 30, 2011 With No Related Allowance Recorded [Member] Retail Sales Finance [Member]	Sep. 30, 2011 With No Related Allowance Recorded [Member] Retail Specialized Lending [Member]	Sep. 30, 2011 Government Guaranteed Loans [Member]	Dec. 31, 2010 Government Guaranteed Loans [Member]	Sep. 30, 2011 Impaired Loans Excluding Acquired Impaired And Government Guaranteed Loans [Member]		Dec. 31, 2010 Impaired Loans Excluding Acquired Impaired And Government Guaranteed Loans [Member]
Recorded Investment				$ 494	$ 512	$ 413	$ 516	$ 301	$ 484	$ 5	$ 4	$ 141	$ 155	$ 63	$ 62	$ 608	[1]	$ 663	[1]	$ 7	$ 5	$ 42	$ 24	$ 149	$ 196	$ 149	$ 175	$ 182	$ 200	$ 0	$ 23	$ 22	$ 28	[1]	$ 25	[1]	$ 1	$ 2	$ 209	$ 115	$ 2,608	[1]	$ 3,043	[1]
Unpaid Principal Balance				513	534	456	565	339	556	5	4	148	161	62	61	625	[1]	690	[1]	10	5	45	24	225	267	194	246	342	300	0	80	69	55	[1]	50	[1]	1	3			3,103	[1]	3,532	[1]
Related Allowance	2,355	2,708	2,611	87	96	72	63	54	75	1	1	32	26	26	25	126	[1]	153	[1]	1	1	19	2																22	14	418	[1]	442	[1]
Average Recorded Investment				343		348		232		4		127		61		582	[1]			5		15		119		105		186		0	27		33	[1]			1	2			2,190	[1]
Interest Income Recognized				$ 1		$ 4		$ 2		$ 0		$ 6		$ 2		$ 20	[1]			$ 0		$ 1									$ 1		$ 1	[1]							$ 38	[1]

[1] Residential mortgage loans exclude $209 million and $115 million in government guaranteed loans and related allowance of $22 million and $14 million as of September 30, 2011 and December 31, 2010, respectively.