Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees, Other Commitments (Details) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Aug. 31, 2008
New Markets Tax Credits [Abstract]
Membership interest in U.S Bank New Markets Tax Credit Fund (in hundredths)			99.90%
Equity contributions to be made to the Fund		$ 285,500,000
Net tax benefits to be received from the Fund		303,800,000
Difference between equity contributions and total benefits received will be recognized over the life of the Fund as net tax benefits		18,300,000
Future equity contributions [Abstract]
Three months ending December 31, 2012	12,786,000	12,786,000
Year ending Dec. 31, 2013	50,822,000	50,822,000
Year ending Dec. 31, 2014	39,059,000	39,059,000
Year ending Dec. 31, 2015	12,975,000	12,975,000
Year ending Dec. 31, 2016	11,890,000	11,890,000
Year ending Dec. 31, 2017	3,292,000	3,292,000
Total future equity contributions	130,824,000	130,824,000
Equity contributions in next 12 months	51,600,000	51,600,000
Equity contributions with an imputed interest rate [Abstract]
Equity contributions - imputed interst rate	6.00%	6.00%
Principal payment schedule above:	130,824,000	130,824,000
Less: unamortized discount	12,291,000	12,291,000
Total	118,533,000	118,533,000
Tax benefits in excess of capital contributions		104,700,000
Tax benefits not utilized	$ 86,500,000	$ 86,500,000
Remaining Period of Recognition of Gross Investment Amortization Expense	5
Period of Recognition of Gross Investment Amortization Expense	10