Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common Class A [Member]
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	38,838,884	38,838,884
Common stock, shares issued (in shares)	26,175,555	26,175,555
Common stock, shares outstanding (in shares)	26,175,555	26,175,555
Common Class B [Member]
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	1,161,116	1,161,116
Common stock, shares issued (in shares)	1,055,560	1,055,560
Common stock, shares outstanding (in shares)	1,055,560	1,055,560

Face amount or stated value per share of common stock.

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