Note 10 - Stock-based Compensation Plan - Stock Option Activity (Details)	3 Months Ended
	Mar. 31, 2023 $ / shares shares
Options outstanding, number of shares (in shares)	580,419
Granted, number of shares (in shares)	90,392
Granted (in dollars per share) | $ / shares	$ 16.06
Exercised, number of shares (in shares)	(25,200)
Exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 6.55
Canceled, number of shares (in shares)	(23,859)
Canceled, weighted average exercise price (in dollars per share) | $ / shares	$ 9.09
Options outstanding, number of shares (in shares)	621,752
Options outstanding, March 31, 2023 (185,246 exercisable) (in dollars per share) | $ / shares	$ 10.04