Purchased Credit Impaired Loans by Credit Quality Indicator (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	$ 38,693	$ 41,430
Commercial and Industrial Loans [Member] | Purchased Credit-Impaired Loans [Member] | Pass [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	260	214
Commercial Real Estate Construction [Member] | Purchased Credit-Impaired Loans [Member] | Pass [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	231	128
Commercial Real Estate Mortgage [Member] | Purchased Credit-Impaired Loans [Member] | Pass [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	512	352
Foreign Loans [Member] | Purchased Credit-Impaired Loans [Member] | Pass [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	154	210
Total Commercial [Member] | Purchased Credit-Impaired Loans [Member] | Pass [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	1,157	904
Commercial and Industrial Loans [Member] | Criticized [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	267	504
Commercial Real Estate Construction [Member] | Criticized [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	1,957	2,821
Commercial Real Estate Mortgage [Member] | Criticized [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	2,288	2,503
Foreign Loans [Member] | Criticized [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	1,347	1,203
Total Commercial [Member] | Criticized [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	5,859	7,031
Commercial and Industrial Loans [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	527	718
Commercial Real Estate Construction [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	2,188	2,949
Commercial Real Estate Mortgage [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	2,800	2,855
Foreign Loans [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	1,501	1,413
Total Commercial [Member] | Purchased Credit-Impaired Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	7,016	7,935
Commercial and Industrial Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	527	718
Commercial Real Estate Mortgage [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	2,800	2,855
Commercial Real Estate Construction [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	2,188	2,949
Foreign Loans [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	1,501	1,413
Total Commercial [Member]
Purchased Credit Impaired Loans by Credit Quality Indicator [Abstract]
Purchased Credit Impaired Loans	$ 7,016	$ 7,935