Note 7 - Share-based Compensation - Stock Option Transactions (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended	12 Months Ended
		Mar. 31, 2023	Dec. 31, 2022
Outstanding, options (in shares)		962,775
Outstanding, weighted average exercise price (in dollars per share)		$ 15.89
Outstanding, weighted average remaining life (Year)		3 years 5 months 15 days	3 years 3 months 3 days
Outstanding, aggregate intrinsic value		$ 30	$ 301
Granted (in shares)	[1]	182,097
Granted, weighted average exercise price (in dollars per share)	[1]	$ 12.04
Exercised (in shares)		(4,604)
Exercised, weighted average exercise price (in dollars per share)		$ 7.60
Lapsed or cancelled (in shares)		(92,457)
Lapsed or cancelled, weighted average exercise price (in dollars per share)		$ 20.77
Outstanding, options (in shares)		1,047,811	962,775
Outstanding, weighted average exercise price (in dollars per share)		$ 14.83	$ 15.89
Exercisable, options (in shares)		536,233
Exercisable, weighted average exercise price, options (in dollars per share)		$ 15.41
Exercisable, weighted average remaining life (Year)		2 years 3 months 3 days
Exercisable, aggregate intrinsic value, options		$ 30

[1] The weighted average grant date fair value of stock options granted was $4.58 per share.