Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Preferred stock, par value (in dollars per share)	$ 0.0001
Preferred stock, shares authorized (in shares)	10,000,000
Preferred stock, shares issued (in shares)	0
Preferred stock, shares outstanding (in shares)	0
Common Class A [Member]
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	15,233,211	14,962,831
Common stock, shares outstanding (in shares)	15,233,211	14,962,831
Common Class B [Member]
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	50,000,000	50,000,000
Common stock, shares issued (in shares)	42,046,356	42,192,250
Common stock, shares outstanding (in shares)	42,046,356	42,192,250