Carrying amount of non-derivative debt instruments designated as net investment hedges.

No definition available.

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- Definition

Forward commitment to sell mortgage loan.

+ References

No definition available.

+ Details

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- Definition

Hedged mortgage loan held for sale.

+ References

No definition available.

+ Details

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- Definition

Unfunded mortgage loan commitments.

+ References

No definition available.

+ Details

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- Definition

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80784-113994

+ Details

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

+ Details

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

No definition available.

+ Details

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- Details

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

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Derivative Instruments - Additional Information (Detail) (USD $)	9 Months Ended	12 Months Ended
	Dec. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Realized and unrealized losses on derivatives classified as cash flow hedges recorded in other comprehensive income (loss)			$ 158,000,000	$ 172,000,000
Forward commitments to sell mortgage loans			8,900,000,000usb_ForwardCommitmentToSellMortgageLoan
Hedged mortgage loans held for sale			4,000,000,000usb_HedgedMortgageLoanHeldForSale
Unfunded mortgage loan commitments			6,900,000,000usb_UnfundedMortgageLoanCommitments
Non-derivative debt instruments designated as net investment hedges			0	0
Fair value of derivatives under collateral agreements in a net liability position			1,000,000,000
Collateral posted by company netted against net liability position			879,000,000
Scenario, Forecast [Member]
Derivative [Line Items]
Estimated loss to be reclassified from other comprehensive income (loss) into earnings	$ 86,000,000	$ 107,000,000