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Note 3 - Securities - Changes in the Allowance for Credit Loss on Held to Maturity Securities (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Balance, HTM | $ 107 |
Recovery of credit losses on HTM securities | (12) | $ 0
Charge-offs of securities, HTM | 0 |
Recoveries, HTM | 0 |
Balance, HTM | 95 | 107
US Treasury Securities [Member] |  |
Balance, HTM | (0) |
Recovery of credit losses on HTM securities | 0 |
Charge-offs of securities, HTM | 0 |
Recoveries, HTM | 0 |
Balance, HTM | (0) | (0)
US Agency and Mortgage-backed Securities [Member] |  |
Balance, HTM | (0) |
Recovery of credit losses on HTM securities | 0 |
Charge-offs of securities, HTM | 0 |
Recoveries, HTM | 0 |
Balance, HTM | (0) | (0)
US States and Political Subdivisions Debt Securities [Member] |  |
Balance, HTM | (0) |
Recovery of credit losses on HTM securities | 0 |
Charge-offs of securities, HTM | 0 |
Recoveries, HTM | 0 |
Balance, HTM | (0) | (0)
Corporate Debt Securities [Member] |  |
Balance, HTM | 107 |
Recovery of credit losses on HTM securities | (12) |
Charge-offs of securities, HTM | 0 |
Recoveries, HTM | 0 |
Balance, HTM | $ 95 | $ 107

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- Definition Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (aaa) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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- Definition Amount of increase in allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity), from recovery. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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- Definition Amount of writeoff of investment in debt security, measured at amortized cost (held-to-maturity), charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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- Definition Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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