Condensed Consolidated Balance Sheet (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Preferred stock, par value	$ 0us-gaap_PreferredStockNoParValue	$ 0us-gaap_PreferredStockNoParValue
Preferred stock, authorized	165,000,000us-gaap_PreferredStockSharesAuthorized	165,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized	3,500,000,000us-gaap_CommonStockSharesAuthorized	3,500,000,000us-gaap_CommonStockSharesAuthorized
Common stock, issued	1,660,600,000us-gaap_CommonStockSharesIssued	1,660,600,000us-gaap_CommonStockSharesIssued
Common stock in treasury, shares	702,100,000us-gaap_TreasuryStockShares	697,700,000us-gaap_TreasuryStockShares

Face amount or stated value per share of common stock.

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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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Face amount per share of no-par value preferred stock nonredeemable or redeemable solely at the option of the issuer.

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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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