Note 6 - Stock Based Awards - Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Outstanding, shares (in shares)	458,700
Outstanding, weighted average exercise price (in dollars per share)	$ 6.63
Outstanding – weighted average remaining contractual term (Year)	6 years 6 months 25 days	6 years 6 months 10 days
Outstanding – aggregate intrinsic value	$ 3,066	$ 1,432
Granted, shares (in shares)	0
Granted, weighted average exercise price (in dollars per share)	$ 0
Exercised, shares (in shares)	0
Exercised, weighted average exercise price (in dollars per share)	$ 0
Forefeited, shares (in shares)	(6,200)
Forefeited, weighted average exercise price (in dollars per share)	$ 11.1
Outstanding, shares (in shares)	452,500	458,700
Outstanding, weighted average exercise price (in dollars per share)	$ 6.57	$ 6.63
Exercisable, shares (in shares)	294,100
Exercisable, weighted average exercise price (in dollars per share)	$ 4.71
Exercisable, weighted average remaining contractual term (Year)	4 years 8 months 15 days
Exercisable, aggregate intrinsic value	$ 2,530