Allowance for Credit Losses (Breakdown of Recorded Investment in Loans Based on the Method for Determining Allowance) (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Individually Evaluated for Impairment	$ 2,979	$ 3,158
Collectively Evaluated for Impairment	97,887	97,551
Loans Acquired With Deteriorated Credit Quality	2,519	2,858
Total	103,385	103,567
Commercial and Industrial [Member]
Individually Evaluated for Impairment	711	708
Collectively Evaluated for Impairment	33,455	33,342
Total	34,166	34,050
Commercial Real Estate - Other [Member]
Individually Evaluated for Impairment	620	691
Collectively Evaluated for Impairment	10,514	10,748
Total	11,134	11,439
Commercial Real Estate - Residential ADC [Member]
Individually Evaluated for Impairment	565	684
Collectively Evaluated for Impairment	2,124	2,713
Total	2,689	3,397
Commercial Specialized Lending [Member]
Individually Evaluated for Impairment	6	4
Collectively Evaluated for Impairment	3,616	3,399
Total	3,622	3,403
Direct Retail Lending [Member]
Individually Evaluated for Impairment	174	177
Collectively Evaluated for Impairment	13,505	13,572
Total	13,679	13,749
Retail Revolving Credit [Member]
Individually Evaluated for Impairment	62	62
Collectively Evaluated for Impairment	2,029	2,065
Total	2,091	2,127
Retail Residential Mortgage [Member]
Individually Evaluated for Impairment	796	803
Collectively Evaluated for Impairment	17,576	16,747
Total	18,372	17,550
Retail Sales Finance [Member]
Individually Evaluated for Impairment	7	5
Collectively Evaluated for Impairment	7,229	7,045
Total	7,236	7,050
Retail Specialized Lending [Member]
Individually Evaluated for Impairment	38	24
Collectively Evaluated for Impairment	4,804	4,526
Total	4,842	4,550
Covered and Other Acquired [Member]
Collectively Evaluated for Impairment	3,035	3,394
Loans Acquired With Deteriorated Credit Quality	2,519	2,858
Total	$ 5,554	$ 6,252