Consolidated Balance Sheet (Unaudited) (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Held-to-maturity securities, fair value	$ 46,022,000,000	$ 45,140,000,000
Securities, pledged as collateral	956,000,000	856,000,000
Mortgage loans, carried at fair value	4,977,000,000	4,774,000,000
Time deposits	100,000	100,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, share-authorized (actual number of shares)	4,000,000,000us-gaap_CommonStockSharesAuthorized	4,000,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued(actual number of shares)	2,125,725,742us-gaap_CommonStockSharesIssued	2,125,725,742us-gaap_CommonStockSharesIssued
Treasury stock, shares (actual number of shares)	345,721,162us-gaap_TreasuryStockShares	339,859,034us-gaap_TreasuryStockShares
Time deposits greater than 250,000	6,000,000,000usb_TimeDeposits250000OrMore	5,000,000,000usb_TimeDeposits250000OrMore
Held-to-maturity Securities [Member]
Securities, pledged as collateral	526,000,000	526,000,000
Available-for-Sale Securities [Member]
Securities, pledged as collateral	390,000,000	330,000,000
Trading Securities [Member]
Securities, pledged as collateral	$ 234,000,000	$ 157,000,000

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Time Deposits 250000 Or More

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Face amount or stated value per share of common stock.

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Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions where counterparty has the right to re-pledge such.

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Fair value of investments in debt securities classified as held-to-maturity.

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Fair value portion of mortgage loans held-for-sale.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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