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Note 2 - Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Total, amortized cost	$ 891,228	$ 793,422
Securities available for sale, gross unrealized gains	4,917	737
Securities available for sale, gross unrealized losses	(41,007)	(63,807)
Fair value	855,138	730,352
US Government Agencies Debt Securities [Member]
Total, amortized cost	632,999	542,676
Securities available for sale, gross unrealized gains	3,356	131
Securities available for sale, gross unrealized losses	(29,573)	(47,226)
Fair value	606,782	495,581
Collateralized Mortgage-Backed Securities [Member]
Total, amortized cost	28,527	31,696
Securities available for sale, gross unrealized gains	12	4
Securities available for sale, gross unrealized losses	(4,866)	(6,332)
Fair value	23,673	25,368
Municipal General Obligation Bonds [Member]
Total, amortized cost	196,099	187,484
Securities available for sale, gross unrealized gains	1,366	513
Securities available for sale, gross unrealized losses	(4,890)	(7,827)
Fair value	192,575	180,170
Municipal Revenue Bonds [Member]
Total, amortized cost	33,103	31,066
Securities available for sale, gross unrealized gains	183	89
Securities available for sale, gross unrealized losses	(1,678)	(2,422)
Fair value	31,608	28,733
Other Debt and Equity Securities [Member]
Total, amortized cost	500	500
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	0	0
Fair value	$ 500	$ 500

X

- Definition

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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