Investment Securities (Details 3) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Accretable balance of the structured investment securities and other investment securities
Balance at beginning of period	$ 117	$ 302	$ 139	$ 292
Additions (a)		66		66
Disposals (a)		(50)		(50)
Accretion	(4)	(8)	(13)	(23)
Other	(6)	(1)	(19)	24
Balance at end of period	$ 107	$ 309	$ 107	$ 309

Certain Securities Acquired In Transfer Accounted For As Debt Securities Accretable Accretion.

Name:	usb_CertainSecuritiesAcquiredInTransferAccountedForAsDebtSecuritiesAccretableAccretion
Namespace Prefix:	usb
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Certain Securities Acquired In Transfer Accounted For As Debt Securities Accretable Additions.

Name:	usb_CertainSecuritiesAcquiredInTransferAccountedForAsDebtSecuritiesAccretableAdditions
Namespace Prefix:	usb
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Certain securities acquired in transfer accounted for as debt securities accretable disposals.

Name:	usb_CertainSecuritiesAcquiredInTransferAccountedForAsDebtSecuritiesAccretableDisposals
Namespace Prefix:	usb
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Certain Securities Acquired In Transfer Accounted For As Debt Securities Acquired.

Name:	usb_CertainSecuritiesAcquiredInTransferAccountedForAsDebtSecuritiesAcquired
Namespace Prefix:	usb
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Certain securities acquired in transfer accounted for as debt securities acquired during period other.

Name:	usb_CertainSecuritiesAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodOther
Namespace Prefix:	usb
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Changes in Accretable Balance for Securities with Evidence of Credit Deterioration at Acquisition.

Name:	usb_ChangesInAccretableBalanceForSecuritiesWithEvidenceOfCreditDeteriorationAtAcquisitionAbstract
Namespace Prefix:	usb
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration