Note 2 - Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Total, amortized cost	$ 680,998	$ 685,646
Securities available for sale, gross unrealized gains	2,206	571
Securities available for sale, gross unrealized losses	(66,112)	(83,281)
Fair value	617,092	602,936
US Government Agencies Debt Securities [Member]
Total, amortized cost	442,496	453,836
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(52,000)	(65,092)
Fair value	390,496	388,744
Collateralized Mortgage-Backed Securities [Member]
Total, amortized cost	35,168	38,002
Securities available for sale, gross unrealized gains	20	19
Securities available for sale, gross unrealized losses	(5,715)	(6,068)
Fair value	29,473	31,953
Municipal General Obligation Bonds [Member]
Total, amortized cost	172,126	163,041
Securities available for sale, gross unrealized gains	1,924	450
Securities available for sale, gross unrealized losses	(6,190)	(9,058)
Fair value	167,860	154,433
Municipal Revenue Bonds [Member]
Total, amortized cost	30,708	30,267
Securities available for sale, gross unrealized gains	262	102
Securities available for sale, gross unrealized losses	(2,207)	(3,063)
Fair value	28,763	27,306
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

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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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-Name Accounting Standards Codification
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