Investment Securities - Gross Unrealized Losses and Fair Value of Company's Investments Securities with Unrealized Losses (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Schedule Of Fair Value And Gross Unrealized Losses [Abstract]
Unrealized Losses Total	$ 17

Available For Sale And Held To Maturity Securities Residential Mortgage Backed Non Agency Continuous Unrealized Loss Position Aggregate Losses Two

No definition available.

Name:	usb_AvailableForSaleAndHeldToMaturitySecuritiesResidentialMortgageBackedNonAgencyContinuousUnrealizedLossPositionAggregateLossesTwo
Namespace Prefix:	usb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant