Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Fixed assets, accumulated depreciation and amortization	$ 1,635	$ 1,639
Preferred stock, par value (usd per share)	$ 1	$ 1
Preferred stock, shares authorized	6,000,000us-gaap_PreferredStockSharesAuthorized	6,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common stock, par value (usd per share)	$ 1	$ 1
Common stock, shares authorized	1,600,000,000us-gaap_CommonStockSharesAuthorized	1,600,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	560,641,640us-gaap_CommonStockSharesIssued	560,641,640us-gaap_CommonStockSharesIssued
Treasury shares, shares	22,229,254us-gaap_TreasuryStockShares	20,499,596us-gaap_TreasuryStockShares

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

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Face amount or stated value per share of common stock.

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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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