Note 13 - Equity Plans - Restricted Stock Unit Activity (Details) - Restricted Stock Unites and Performance Stock Units [Member] - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Beginning balance (in shares)	576,867	610,540	636,086
Beginning balance (in dollars per share)	$ 18.29	$ 18.14	$ 19.25
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period	55,558	20,604	70,588
Granted (in dollars per share)	$ 25.56	$ 23.29	$ 11.92
Converted into shares (in shares)	(5,841)	(49,191)	(94,161)
Converted into shares (in dollars per share)	$ 18.16	$ 18.67	$ 20.27
Forfeited (in shares)	(9,066)	(5,086)	(1,973)
Forfeited (in dollars per share)	$ 17.52	$ 17.55	$ 18.14
Outstanding at December 31 (in shares)	617,518	576,867	610,540
Outstanding at December 31 (in dollars per share)	$ 18.95	$ 18.29	$ 18.14
Vested at December 31 (in shares)	423,941	370,771	375,692
Vested at December 31 (in dollars per share)	$ 19.24	$ 18.78	$ 18.88