Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Sep. 30, 2019	Dec. 31, 2018
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	19,585,394	19,243,651
Common stock, shares outstanding (in shares)	19,585,394	19,243,651
Series A Convertible Preferred Stock [Member]
Preferred stock, shares authorized (in shares)	22,000	22,000
Preferred stock, shares issued (in shares)	21,660	22,000
Preferred stock, shares outstanding (in shares)	21,660	22,000

Face amount or stated value per share of common stock.

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