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Note 2 - Securities - Debt Securities by Maturity (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Due in one year or less, amortized cost | $ 57,724 |
Due in one year or less, fair value | 56,289 |
Due from one to five years, amortized cost | 261,591 |
Due from one to five years, fair value | 241,758 |
Due from five to ten years, amortized cost | 279,722 |
Due from five to ten years, fair value | 243,791 |
Due after ten years, amortized cost | 46,293 |
Due after ten years, fair value | 45,281 |
Total, amortized cost | 680,998 | $ 685,646
Fair value | 617,092 | 602,936
Collateralized Mortgage-Backed Securities [Member] |  |
No single maturity, amortized cost | 35,168 |
No single maturity, fair value | 29,473 |
Total, amortized cost | 35,168 | 38,002
Fair value | 29,473 | 31,953
Other Debt and Equity Securities [Member] |  |
No single maturity, amortized cost | 500 |
No single maturity, fair value | 500 |
Total, amortized cost | 500 | 500
Fair value | $ 500 | $ 500

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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-3 + Details
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-3 + Details
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