Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2019	Dec. 31, 2018	Aug. 02, 2017
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)	557,631	481,091
Common stock, shares outstanding (in shares)	557,631	481,091
Series A Convertible Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	22,000	22,000
Preferred stock, shares issued (in shares)	18,954	22,000
Preferred stock, shares outstanding (in shares)	18,954	22,000

Face amount or stated value per share of common stock.

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