Note 10 - Common Stock and Stock-based Compensation Plans - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands		9 Months Ended		12 Months Ended
		Sep. 30, 2022		Dec. 31, 2021
Outstanding, Number of shares (in shares)	[1]	126,000
Outstanding, Weighted average exercise price (in dollars per share)		$ 20.06
Outstanding, Weighted average remaining contractual term (Year)		2 years 2 months 12 days	[2]	2 years 7 months 6 days
Outstanding, Aggregated intrinsic value		$ 664	[2]	$ 2,921
Granted, Number of shares (in shares)	[1]	0
Exercised, Number of shares (in shares)	[1]	(17,000)
Exercised, Weighted average exercise price (in dollars per share)		$ 18.08
Forfeited or expired, Number of shares (in shares)	[1]	0
Outstanding, Number of shares (in shares)	[1]	109,000	[2]	126,000
Outstanding, Weighted average exercise price (in dollars per share)		$ 20.37	[2]	$ 20.06
Exercisable, Number of shares (in shares)	[1],[3]	109,000
Exercisable, Weighted average exercise price (in dollars per share)	[3]	$ 20.37
Exercisable, Weighted average remaining contractual term (Year)	[3]	2 years 2 months 12 days
Exercisable, Aggregated intrinsic value	[3]	$ 664

[1] The SAR units are convertible for a maximum number of shares of the Company’s common stock equal to 75% of the SAR units subject to the grant.

[2] Due to the ceiling imposed on the SAR grants, the outstanding amount equals a maximum of 108,250 shares of the Company’s common stock issuable upon exercise.

[3] Due to the ceiling imposed on the SAR grants, the exercisable amount equals a maximum of 108,250 shares of the Company’s common stock issuable upon exercise.