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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

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- 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). + References 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 + Details
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- Definition Amount, before tax, of unrealized loss 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). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 + Details
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