Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	200,000,000	200,000,000
Common stock, issued (in shares)	40,732,409	36,162,433
Common stock, outstanding (in shares)	40,718,240	36,148,264
Treasury Stock, Shares, Ending Balance	14,169	14,169

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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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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