Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Convertible Preferred Stock, Par Value (in dollars per share)	$ 0.00067	$ 0.00067
Convertible Preferred Stock, Shares Authorized (in shares)	50,000,000	50,000,000
Convertible Preferred Stock, Shares Issued (in shares)	0	0
Convertible Preferred Stock, Shares Outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.00067	$ 0.00067
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	239,963,788	225,885,682

Face amount or stated value per share of common stock.

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