Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees, Other Commitments (Details) - NMTC [Member] - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2015	Aug. 31, 2008
Other Commitments [Line Items]
Membership interest in U.S Bank New Markets Tax Credit Fund (in hundredths)			99.90%
Equity contributions to be made to the Fund	$ 283,700
Net tax benefits to be received from the Fund	302,000
Difference between equity contributions and total benefits received will be recognized over the life of the Fund as net tax benefits	18,300
Future equity contributions to the NMTC Fund [Abstract]
Six months ending Dec. 31, 2015	3,629	$ 3,629
Year ending Dec. 31, 2016	2,707	2,707
Year ending Dec. 31, 2017	2,707	2,707
Total	9,043	9,043
Total future equity contributions	9,043	9,043
Future equity contributions due within the next 12 months	3,600	3,600
Tax Benefits in Excess of Capital Contributions	25,600	25,600
Tax benefits not utilized	$ 118,800	$ 118,800
Equity contributions, imputed interest rate 6%[Abstract]
Equity contributions - imputed interest rate (in hundredths)	6.00%	6.00%
Principal payment schedule above:	$ 9,043	$ 9,043
Less: unamortized discount	594	594
Total	$ 8,449	$ 8,449
Period of recognition of gross investment amortization expense (in years)		9 years
Remaining period of recognition of gross investment amortization expense (in years)		2 years