Authorized Common Stock Repurchase Programs (Detail)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Class of Stock [Line Items]
Common Stock, Shares Issued, Ending Balance	1,996,537,778us-gaap_CommonStockSharesIssued	1,996,537,778us-gaap_CommonStockSharesIssued
Common Stock, Treasury Shares, Ending Balance	(332,896,779)us-gaap_TreasuryStockShares	(291,141,184)us-gaap_TreasuryStockShares
Common Class A
Class of Stock [Line Items]
Common Stock, Shares Issued, Beginning Balance	1,996,537,778	1,996,537,778	1,996,537,778
Shares repurchased	(51,931,864.0000000000)	(82,799,448.0000000000)
Exercise of stock options and issuance of other stock awards	0	0	0
Common Stock, Shares Issued, Ending Balance	1,996,537,778	1,996,537,778	1,996,537,778
Common Stock, Treasury Shares, Beginning Balance	(291,141,184)	(218,541,936)	(228,641,089)
Exercise of stock options and issuance of other stock awards	10,176,269	10,200,200	10,099,153
Common Stock, Treasury Shares, Ending Balance	(332,896,779)	(291,141,184)	(218,541,936)
Common Stock, Shares Outstanding, Beginning Balance	1,705,396,594	1,777,995,842	1,767,896,689
Shares repurchased	(51,931,864.0000000000)	(82,799,448.0000000000)
Exercise of stock options and issuance of other stock awards	10,176,269	10,200,200	10,099,153
Common Stock, Shares Outstanding, Ending Balance	1,663,640,999	1,705,396,594	1,777,995,842

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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 shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

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

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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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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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Number of shares that have been repurchased during the period and are being held in treasury.

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