Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00
Preferred stock, shares authorized (in shares)	10,000,000us-gaap_PreferredStockSharesAuthorized	10,000,000us-gaap_PreferredStockSharesAuthorized
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common Stock, shares authorized (in shares)	250,000,000us-gaap_CommonStockSharesAuthorized	150,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	118,646,261us-gaap_CommonStockSharesIssued	101,430,853us-gaap_CommonStockSharesIssued
Common stock, shares outstanding (in shares)	114,501,014us-gaap_CommonStockSharesOutstanding	97,482,998us-gaap_CommonStockSharesOutstanding
Common stock in treasury, shares (in shares)	4,145,247us-gaap_TreasuryStockShares	3,947,855us-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 or stated value per share of 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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