Earnings Per Share - Components of Earnings Per Share (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Earnings Per Share [Abstract]
Net income attributable to U.S. Bancorp	$ 1,495	$ 1,484	$ 2,892	$ 2,912
Preferred dividends	(61)	(64)	(121)	(128)
Impact of preferred stock redemption		(8)		(8)
Earnings allocated to participating stock awards	(7)	(7)	(13)	(13)
Net income applicable to U.S. Bancorp common shareholders	$ 1,427	$ 1,405	$ 2,758	$ 2,763
Average common shares outstanding	1,811	1,843	1,815	1,851
Net effect of the exercise and assumed purchase of stock awards	10	10	10	9
Average diluted common shares outstanding	1,821	1,853	1,825	1,860
Earnings per common share	$ 0.79	$ 0.76	$ 1.52	$ 1.49
Diluted earnings per common share	$ 0.78	$ 0.76	$ 1.51	$ 1.49