CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Preferred stock, par value (USD per share)	$ 0.001	$ 0.001
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value (USD per share)	$ 0.001	$ 0.001
Common stock, authorized	250,000us-gaap_CommonStockSharesAuthorized	250,000us-gaap_CommonStockSharesAuthorized
Common stock, issued	36,106us-gaap_CommonStockSharesIssued	36,099us-gaap_CommonStockSharesIssued
Common stock, outstanding	36,106us-gaap_CommonStockSharesOutstanding	36,099us-gaap_CommonStockSharesOutstanding
Preferred stock, Series A
Preferred stock, authorized	200	200
Preferred stock, Undesignated series
Preferred stock, authorized	59,800	59,800

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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