CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
CONDENSED CONSOLIDATED BALANCE SHEETS
Property and equipment, Accumulated depreciation	$ 62,462	$ 60,271
Common stock, par value	$ 0	$ 0
Common stock, shares authorized (in shares)	180,000,000	180,000,000
Common stock, issued (in shares)	60,677,742	60,672,034
Common stock, outstanding (in shares)	59,536,213	60,672,034
Treasury stock (in shares)	1,141,529

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 per share of no-par value 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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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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