Note 17 - Earnings Per Share - Computation of Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net income attributable to common shares	$ 82,217	$ 61,063	$ 59,021
Weighted average common shares outstanding (in shares)	16,015,678	15,859,889	15,986,857
Basic earnings per common share (in dollars per share)	$ 5.13	$ 3.85	$ 3.69
Net income	$ 82,217	$ 61,063	$ 59,021
Weighted average common shares outstanding for basic earnings per common share (in shares)	16,015,678	15,859,889	15,986,857
Add: Dilutive effects of share-based awards (in shares)	0	12	446
Average shares and dilutive potential common shares (in shares)	16,015,678	15,859,901	15,987,303
Diluted earnings per common share (in dollars per share)	$ 5.13	$ 3.85	$ 3.69