Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares $ / shares in Thousands	Sep. 30, 2018	Dec. 31, 2017
Preferred stock, no par value (in dollars per share)	$ 0	$ 0
Preferred stock, shares authorized (in shares)	10,000	10,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized (in shares)	200,000	200,000
Common stock, shares issued (in shares)	70,312	57,630
Common stock, shares outstanding (in shares)	70,312	57,630

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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Face amount per share of no-par value 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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