Note 16 - Stock-Based Compensation - Stock Option Plans (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Stock-Based Compensation
Outstanding, shares (in shares)	367,998	407,763	426,913
Outstanding, Weighted average exercise price (in dollars per share)	$ 24.46	$ 22.24	$ 20.14
Granted, shares (in shares)	22,400	22,150	23,350
Granted, Weighted average exercise price (in dollars per share)	$ 53.87	$ 43.61	$ 39.12
Exercised, shares (in shares)	(41,695)	(60,317)	(41,650)
Exercised, Weighted average exercise price (in dollars per share)	$ 14.07	$ 15.76	$ 10.67
Forfeited, shares (in shares)	(2,025)	(1,598)	(850)
Forfeited, Weighted average exercise price (in dollars per share)	$ 26.72	$ 38.50	$ 19.94
Outstanding, shares (in shares)	346,678	367,998	407,763
Outstanding, Weighted average exercise price (in dollars per share)	$ 27.60	$ 24.46	$ 22.24
Exercisable, , shares (in shares)	295,077	318,266	354,899
Weighted-average grant date fair value (in dollars per share)	$ 13.97	$ 10.85	$ 10.07