Note 2 - Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Total, amortized cost	$ 1,166,037	$ 1,132,603
Securities available for sale, gross unrealized gains	2,995	6,483
Securities available for sale, gross unrealized losses	(43,503)	(36,856)
Fair value	1,125,529	1,102,230
US Treasury Securities [Member]
Total, amortized cost	55,805	55,501
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(706)	0
Fair value	55,099	55,501
US Government Agencies Debt Securities [Member]
Total, amortized cost	716,342	661,841
Securities available for sale, gross unrealized gains	1,008	4,343
Securities available for sale, gross unrealized losses	(29,842)	(26,411)
Fair value	687,508	639,773
Collateralized Mortgage-Backed Securities [Member]
Total, amortized cost	75,258	80,475
Securities available for sale, gross unrealized gains	7	14
Securities available for sale, gross unrealized losses	(6,066)	(4,727)
Fair value	69,199	75,762
Municipal General Obligation Bonds [Member]
Total, amortized cost	213,901	217,283
Securities available for sale, gross unrealized gains	1,804	1,946
Securities available for sale, gross unrealized losses	(4,532)	(4,166)
Fair value	211,173	215,063
Municipal Revenue Bonds [Member]
Total, amortized cost	65,546	66,376
Securities available for sale, gross unrealized gains	176	180
Securities available for sale, gross unrealized losses	(2,094)	(1,552)
Fair value	63,628	65,004
Other Debt and Equity Securities [Member]
Total, amortized cost	39,185	51,127
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(263)	0
Fair value	$ 38,922	$ 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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