Basis of Presentation - Line of Business Financial Performance (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Line Of Business Financial Performance [Line Items]
Revenue generated from contracts with customers included in noninterest income	$ 1,800	$ 1,700
Payment Services [Member]
Line Of Business Financial Performance [Line Items]
Rewards and rebate costs and certain partner payments included in noninterest income	$ 534	$ 468

Rewards and rebate costs and certain partner payments included in noninterest income.

No definition available.

Name:	usb_RewardsAndRebateCostsAndCertainPartnerPaymentsIncludedInNoninterestIncome
Namespace Prefix:	usb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration