Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Preferred Stock, par value per share (in dollars per share)	$ 1	$ 1.00
Preferred Stock, shares authorized (in shares)	4,000,000us-gaap_PreferredStockSharesAuthorized	4,000,000us-gaap_PreferredStockSharesAuthorized
Common Stock, par value per share (in dollars per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (in shares)	500,000,000us-gaap_CommonStockSharesAuthorized	500,000,000us-gaap_CommonStockSharesAuthorized
Common Stock, Shares, Issued	402,329,325us-gaap_CommonStockSharesIssued	399,841,717us-gaap_CommonStockSharesIssued
Treasury Stock, Shares	37,635,890us-gaap_TreasuryStockShares	37,600,051us-gaap_TreasuryStockShares

Face amount or stated value per share of common stock.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

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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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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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

-Publisher FASB

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-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.28)

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

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

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-Subparagraph (SX 210.5-02.28,29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

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