Note 3 - Stocked-based Compensation - Stock Option Activity (Details) - $ / shares	9 Months Ended
	Sep. 30, 2023
Options outstanding, Options (in shares)	410,615
Options outstanding, Weighted average price (in dollars per share)	$ 3.50
Granted, Options (in shares)	46,400
Granted, Weighted average price (in dollars per share)	$ 4.23
Exercised, Options (in shares)	(134,250)
Exercised, Weighted average price (in dollars per share)	$ 3.27
Canceled/expired/forfeited, Options (in shares)	13,333
Canceled/expired/forfeited, Weighted average price (in dollars per share)	$ 3.61
Options, Options (in shares)	309,432
Options outstanding, Weighted average price (in dollars per share)	$ 3.70
Options exercisable, Options (in shares)	253,231
Options exercisable, Weighted average price (in dollars per share)	$ 3.59