Note 3 - Shareholders' Equity - Information About Stock Options (Details)	3 Months Ended
	Mar. 31, 2024 $ / shares shares
Options outstanding, options (in shares) | shares	292,766
Options outstanding, weighted average exercise price (in dollars per share) | $ / shares	$ 3.71
Exercised, options (in shares) | shares	(226,666)
Exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 3.59
Options outstanding, options (in shares) | shares	66,100
Options outstanding, weighted average exercise price (in dollars per share) | $ / shares	$ 4.12
Options exercisable, options (in shares) | shares	9,899
Options exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 3.7