Condensed Consolidated Statements Of Financial Position (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Property, plant and equipment, accumulated depreciation	$ 15,880	$ 15,689
Other assets, accumulated amortization	$ 506	$ 479
Common stock, par value	$ 5.00	$ 5.00
Common stock, authorized	1,200,000,000us-gaap_CommonStockSharesAuthorized	1,200,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	1,012,261,159us-gaap_CommonStockSharesIssued	1,012,261,159us-gaap_CommonStockSharesIssued
Treasury stock, shares	318,257,541us-gaap_TreasuryStockShares	305,533,606us-gaap_TreasuryStockShares

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.14)

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 02

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For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

+ References

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-Topic 985

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Face amount or stated value per share of common stock.

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

-Publisher FASB

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-Topic 210

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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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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