Purchased Loans (Purchased Impaired Loans Balances) (Details) (Purchased Impaired Loans [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 8,083	[1]	$ 6,667	[2]
Outstanding Balance	9,483	[1]	7,521	[2]
Total commercial lending [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,532	[1]	852	[2]
Outstanding Balance	2,153	[1]	988	[2]
Total consumer lending [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	6,551	[1]	5,815	[2]
Outstanding Balance	7,330	[1]	6,533	[2]
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	405	[1]	140	[2]
Outstanding Balance	686	[1]	245	[2]
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,127	[1]	712	[2]
Outstanding Balance	1,467	[1]	743	[2]
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	3,777	[1]	3,049	[2]
Outstanding Balance	4,041	[1]	3,128	[2]
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	2,774	[1]	2,766	[2]
Outstanding Balance	$ 3,289	[1]	$ 3,405	[2]

[1] Represents National City and RBC Bank (USA) acquisitions.

[2] Represents National City acquisition.