Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	30,000,000	30,000,000
Common stock, shares issued (in shares)	17,211,498	16,830,930
Treasury stock, common shares (in shares)	273,937	273,937

Face amount or stated value per share of common stock.

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