Note 13 - Stock-based Compensation Plan - Stock Option Activity (Details) - $ / shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Options outstanding, number of shares (in shares)	408,869
Options outstanding, weighted average exercise price (in dollars per share)		$ 9.07
Granted, number of shares (in shares)	202,540
Granted, weighted average exercise price (in dollars per share)		8.45
Exercised, number of shares (in shares)	(8,060)
Exercised, weighted average exercise price (in dollars per share)		4.74
Canceled, number of shares (in shares)	(22,930)
Canceled, weighted average exercise price (in dollars per share)		9.10
Options outstanding, number of shares (in shares)	580,419
Options outstanding, weighted average exercise price (in dollars per share)		$ 8.91