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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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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.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Topic 505

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- Definition

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.

+ References

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

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

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Equity, Share Activity Rollforward (Details)	3 Months Ended		1 Months Ended
Equity, Share Activity Rollforward (Details)	Mar. 31, 2015	Mar. 31, 2014	Apr. 30, 2015	Dec. 31, 2014
Share Activity
Treasury stock, shares, beginning balance				(159,202,872)us-gaap_TreasuryStockShares
Treasury stock, shares, ending balance	(163,184,575)us-gaap_TreasuryStockShares			(159,202,872)us-gaap_TreasuryStockShares
Common Stock [Member]
Share Activity
Common stock, shares, beginning balance	673,000,000	673,000,000
Stock issuances, shares	0	0
Common stock, shares, ending balance	673,000,000	673,000,000
Treasury Stock [Member]
Share Activity
Treasury stock, shares, beginning balance	(159,000,000)	(138,000,000)
Stock issuances, shares	2,000,000	2,000,000
Treasury stock, shares, ending balance	(163,000,000)	(140,000,000)
Treasury Stock [Member] \| Stock-Based Compensation Plans Repurchase Program [Member]
Share Activity
Stock repurchases, shares	(1,000,000)	0
Treasury Stock [Member] \| Common Stock Repurchase Program [Member]
Share Activity
Stock repurchases, shares	(5,000,000)	(4,000,000)
Subsequent Event [Member] \| Treasury Stock [Member]
Share Activity
Stock repurchases, shares			(1,700,000)