Note 15 - Comprehensive Income - Accumulated Other Comprehensive (Loss) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance	$ 1,178,751	$ 1,124,212	$ 915,310	$ 731,190
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Balance	(61,775)	(484)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Balance	32,360	2,406
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	(2,949)	(3,326)
AOCI Attributable to Parent [Member]
Balance	$ (32,364)	$ (1,404)	$ 2,797	$ (1,147)