Earnings Per Share - Components of Earnings Per Share (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Net income attributable to U.S. Bancorp	$ 1,468	$ 1,474	$ 4,380	$ 4,227
Preferred dividends	(61)	(64)	(189)	(174)
Impact of preferred stock redemption			(8)
Earnings allocated to participating stock awards	(7)	(6)	(20)	(19)
Net income applicable to U.S. Bancorp common shareholders	$ 1,400	$ 1,404	$ 4,163	$ 4,034
Average common shares outstanding	1,832	1,886	1,844	1,892
Net effect of the exercise and assumed purchase of stock awards	11	11	10	9
Average diluted common shares outstanding	1,843	1,897	1,854	1,901
Earnings per common share	$ 0.76	$ 0.74	$ 2.26	$ 2.13
Diluted earnings per common share	$ 0.76	$ 0.74	$ 2.25	$ 2.12