Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Consolidated Balance Sheets
Accumulated depreciation of property and equipment (in dollars)	$ 12,028	$ 11,520
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	125,000,000us-gaap_CommonStockSharesAuthorized	125,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	96,375,015us-gaap_CommonStockSharesIssued	95,556,277us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	96,375,015us-gaap_CommonStockSharesOutstanding	95,556,277us-gaap_CommonStockSharesOutstanding

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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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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