Note 2 - Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Total, amortized cost	$ 1,176,200	$ 1,132,603
Securities available for sale, gross unrealized gains	22	6,483
Securities available for sale, gross unrealized losses	(78,206)	(36,856)
Fair value	1,098,016	1,102,230
US Treasury Securities [Member]
Total, amortized cost	51,958	55,501
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(1,544)	0
Fair value	50,414	55,501
US Government Agencies Debt Securities [Member]
Total, amortized cost	729,057	661,841
Securities available for sale, gross unrealized gains	1	4,343
Securities available for sale, gross unrealized losses	(47,056)	(26,411)
Fair value	682,002	639,773
Collateralized Mortgage-Backed Securities [Member]
Total, amortized cost	79,706	80,475
Securities available for sale, gross unrealized gains	0	14
Securities available for sale, gross unrealized losses	(10,994)	(4,727)
Fair value	68,712	75,762
Municipal General Obligation Bonds [Member]
Total, amortized cost	213,234	217,283
Securities available for sale, gross unrealized gains	11	1,946
Securities available for sale, gross unrealized losses	(14,235)	(4,166)
Fair value	199,010	215,063
Municipal Revenue Bonds [Member]
Total, amortized cost	65,463	66,376
Securities available for sale, gross unrealized gains	10	180
Securities available for sale, gross unrealized losses	(3,826)	(1,552)
Fair value	61,647	65,004
Other Debt and Equity Securities [Member]
Total, amortized cost	36,782	51,127
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(551)	0
Fair value	$ 36,231	$ 51,127

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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