Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares $ / shares in Thousands	Jun. 30, 2018	Dec. 31, 2017
Preferred stock, par value (in dollars per share)	$ 0	$ 0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, shares outstanding (in shares)	35,819,772	35,439,272

Face amount per share of no-par value common stock.

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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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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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