Note 15 - Accumulated Other Comprehensive Income (Loss) - Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Balance	$ 760,432
Balance	858,103	$ 760,432
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Balance	(115,648)	(7,657)	$ 9,309
Net current period other comprehensive income (loss)	22,970	(107,991)	(16,966)
Balance	(92,678)	(115,648)	(7,657)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Balance	0	0	(121)
Net current period other comprehensive income (loss)	(179)	0	121
Balance	(179)	0	0
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	112	(283)	(447)
Net current period other comprehensive income (loss)	(53)	395	164
Balance	59	112	(283)
AOCI Attributable to Parent [Member]
Balance	(115,536)	(7,940)	8,741
Net current period other comprehensive income (loss)	22,738	(107,596)	(16,681)
Balance	$ (92,798)	$ (115,536)	$ (7,940)