CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Shareholders’ equity:
Preferred stock, par value (in dollars per share)	$ 0.02	$ 0.02
Preferred stock authorized (in shares)	1,000,000	1,000,000
Common stock per value (in dollars per share)	$ 0.02	$ 0.02
Common stock authorized (in shares)	58,000,000	58,000,000
Common stock issued (in shares)	28,017,033	22,982,955
Common stock outstanding (in shares)	26,855,578	21,917,357
Treasury stock at cost (in shares)	1,161,455	1,065,598

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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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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