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Note 2 - Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Total, amortized cost	$ 749,090	$ 680,998
Securities available for sale, gross unrealized gains	3,850	2,206
Securities available for sale, gross unrealized losses	(49,565)	(66,112)
Fair value	703,375	617,092
US Government Agencies Debt Securities [Member]
Total, amortized cost	505,005	442,496
Securities available for sale, gross unrealized gains	1,823	0
Securities available for sale, gross unrealized losses	(37,507)	(52,000)
Fair value	469,321	390,496
Collateralized Mortgage-Backed Securities [Member]
Total, amortized cost	32,549	35,168
Securities available for sale, gross unrealized gains	15	20
Securities available for sale, gross unrealized losses	(4,964)	(5,715)
Fair value	27,600	29,473
Municipal General Obligation Bonds [Member]
Total, amortized cost	180,326	172,126
Securities available for sale, gross unrealized gains	1,778	1,924
Securities available for sale, gross unrealized losses	(5,259)	(6,190)
Fair value	176,845	167,860
Municipal Revenue Bonds [Member]
Total, amortized cost	30,710	30,708
Securities available for sale, gross unrealized gains	234	262
Securities available for sale, gross unrealized losses	(1,835)	(2,207)
Fair value	29,109	28,763
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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