Earnings Per Share - Components of Earnings Per Share (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Abstract]
Net income attributable to U.S. Bancorp	$ 1,397	$ 1,428
Preferred dividends	(60)	(64)
Earnings allocated to participating stock awards	(6)	(6)
Net income applicable to U.S. Bancorp common shareholders	$ 1,331	$ 1,358
Average common shares outstanding	1,818	1,858
Net effect of the exercise and assumed purchase of stock awards	10	9
Average diluted common shares outstanding	1,828	1,867
Earnings per common share	$ 0.73	$ 0.73
Diluted earnings per common share	$ 0.73	$ 0.73