Earnings Per Share - Components of Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2019		Jun. 30, 2018		Jun. 30, 2019		Jun. 30, 2018
Earnings Per Share [Abstract]
Net income attributable to U.S. Bancorp	$ 1,821		$ 1,750		$ 3,520		$ 3,425
Preferred dividends	(72)	[1]	(64)	[2]	(151)	[3]	(134)	[4]
Earnings allocated to participating stock awards	(8)		(8)		(15)		(16)
Net income applicable to U.S. Bancorp common shareholders	$ 1,741		$ 1,678		$ 3,354		$ 3,275
Average common shares outstanding	1,590		1,642		1,596		1,647
Net effect of the exercise and assumed purchase of stock awards	2		4		3		4
Average diluted common shares outstanding	1,592		1,646		1,599		1,651
Earnings per common share	$ 1.09		$ 1.02		$ 2.10		$ 1.99
Diluted earnings per common share	$ 1.09		$ 1.02		$ 2.10		$ 1.98

[1] Reflects dividends declared per share on the Company’s Series A, Series B, Series F, Series H, Series I and Series K Non-Cumulative Perpetual Preferred Stock of $914.234, $221.18, $406.25, $321.88, $640.625 and $343.75, respectively.

[2] Reflects dividends declared per share on the Company's Series A, Series B, Series F, Series H and Series I Non-Cumulative Perpetual Preferred Stock of $884.722, $221.18, $406.25, $321.88 and $640.625, respectively.

[3] Reflects dividends declared per share on the Company’s Series A, Series B, Series F, Series H, Series I, Series J and Series K Non-Cumulative Perpetual Preferred Stock of $1,866.062, $439.93, $812.50, $643.76, $640.625, $662.50 and $687.50, respectively.

[4] Reflects dividends declared per share on the Company's Series A, Series B, Series F, Series H, Series I and Series J Non-Cumulative Perpetual Preferred Stock of $1,759.722, $439.93, $812.50, $643.76, 640.625 and $662.50, respectively.