Consolidated Balance Sheets Parenthetical (USD $)	Dec. 31, 2014	Dec. 31, 2013
CONSOLIDATED BALANCE SHEETS [Abstract]
Preferred stock, par value (dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	1,000us-gaap_PreferredStockSharesAuthorized	1,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, outstanding (in shares)	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value (dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	350,000us-gaap_CommonStockSharesAuthorized	350,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	102,069us-gaap_CommonStockSharesIssued	101,276us-gaap_CommonStockSharesIssued
Common stock, outstanding (in shares)	100,126us-gaap_CommonStockSharesOutstanding	99,312us-gaap_CommonStockSharesOutstanding
Treasury stock, shares (in shares)	1,943us-gaap_TreasuryStockShares	1,964us-gaap_TreasuryStockShares

Face amount or stated value per share of common stock.

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

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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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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.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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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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