Note 4 - Stock-based Compensation - Summary of Option Activity (Details) - Share-Based Payment Arrangement, Option [Member] - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Balance (in shares)		1,111	721
Options outstanding, weighted average exercise price (in dollars per share)		$ 17.99	$ 15.77
Options outstanding, weighted average grant date fair value (in dollars per share)		$ 8.31	$ 7.26
Options outstanding, weighted average contractual ife (Year)	8 years		9 years	9 years 9 months 18 days
Options outstanding, aggregate intrinsic value	$ 17,968	$ 17,968	$ (9,382)	$ (692)
Options granted (in shares)		0	450
Granted, weighted average exercise price (in dollars per share)		$ 0	$ 21.24
Options granted, weighted average grant date fair value (in dollars per share)			$ 9.85
Options exercised (in shares)		(24)	0
Exercised, weighted average exercise price (in dollars per share)		$ 15.77	$ 0
Options exercised, weighted average grant date fair value (in dollars per share)		$ 4.90
Options forfeited (in shares)		0	(60)
Forfeited, weighted average exercise price (in dollars per share)		$ 0	$ 15.77
Options forfeited, weighted average grant date fair value (in dollars per share)			$ 7.26
Options outstanding, aggregate intrinsic value	$ (17,968)	$ (17,968)	$ 9,382	$ 692
Balance (in shares)	1,087	1,087	1,111	721
Options outstanding, weighted average exercise price (in dollars per share)	$ 18.04	$ 18.04	$ 17.99	$ 15.77
Options outstanding, weighted average grant date fair value (in dollars per share)	$ 8.39	$ 8.39	$ 8.31	$ 7.26
Exercisable (in shares)	141	141
Exercisable, weighted average exercise price (in dollars per share)	$ 15.77	$ 15.77
Exercisable, weighted average grant date fair value (in dollars per share)	$ 4.90	$ 4.90
Exercisable, weighted average contractual life (Year)	7 years 10 months 24 days
Exercisable, options outstanding, aggregate intrinsic valueo	$ 2,649	$ 2,649