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Note 2 - Securities - Debt Securities by Maturity (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Due in one year or less, weighted average yield | 0.76% |
Due in one year or less, amortized cost | $ 21,278,000 |
Due in one year or less, fair value | $ 20,732,000 |
Due from one to five years, weighted average yield | 1.22% |
Due from one to five years, amortized cost | $ 249,262,000 |
Due from one to five years, fair value | $ 227,357,000 |
Due from five to ten years, weighted average yield | 1.88% |
Due from five to ten years, amortized cost | $ 318,700,000 |
Due from five to ten years, fair value | $ 271,652,000 |
Due after ten years, weighted average yield | 3.03% |
Due after ten years, amortized cost | $ 57,904,000 |
Due after ten years, fair value | $ 50,742,000 |
Weighted average yield | 1.72% |
Amortized cost | $ 685,646,000 | $ 597,463,000
Fair value | $ 602,936,000 | 592,743,000
Collateralized Mortgage-Backed Securities [Member] |  |
No single maturity, weighted average yield | 2.10% |
No single maturity, amortized cost | $ 38,002,000 |
No single maturity, fair value | 31,953,000 |
Amortized cost | 38,002,000 | 41,906,000
Fair value | $ 31,953,000 | 41,803,000
Other Debt and Equity Securities [Member] |  |
No single maturity, weighted average yield | 4.94% |
No single maturity, amortized cost | $ 500,000 |
No single maturity, fair value | 500,000 |
Amortized cost | 500,000 | 500,000
Fair value | $ 500,000 | $ 500,000

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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). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
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