Litigation, Other Commitments and Contingencies, and Disclosures about Guarantees, New Markets Tax Credits (Details) - New Markets Tax Credit [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	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	$ 283.7
Net tax benefits to be received from the Fund	302.0
Difference between equity contributions and total benefits received will be recognized over the life of the Fund as net tax benefits	18.3
Tax benefits in excess of capital contributions	16.7
Tax benefits not utilized	$ 116.8
Period (in years) over which gross investment amortization expense is recognized	9 years
Remaining period (in years) of recognition of gross investment amortization expense	2 years