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Note 2 - Securities - Changes in the Allowance for Credit Loss on Held to Maturity Securities (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Balance, HTM | $ 107 | $ 0
Provision for credit losses, HTM | (3) | 10
Charge-offs of securities, HTM | 0 | 0
Recoveries, HTM | 0 | (37)
Balance, HTM | 104 | 107
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] |  |
Balance, HTM |  | 134
US Treasury Securities [Member] |  |
Balance, HTM | (0) | 0
Provision for credit losses, HTM | 0 | 0
Charge-offs of securities, HTM | 0 | 0
Recoveries, HTM | 0 | 0
Balance, HTM | (0) | (0)
US Treasury Securities [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] |  |
Balance, HTM |  | 0
US Agency and Mortgage-backed Securities [Member] |  |
Balance, HTM | (0) | 0
Provision for credit losses, HTM | 0 | 0
Charge-offs of securities, HTM | 0 | 0
Recoveries, HTM | 0 | 0
Balance, HTM | (0) | (0)
US Agency and Mortgage-backed Securities [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] |  |
Balance, HTM |  | 0
US States and Political Subdivisions Debt Securities [Member] |  |
Balance, HTM | (0) | 0
Provision for credit losses, HTM | 1 | 0
Charge-offs of securities, HTM | 0 | 0
Recoveries, HTM | 0 | 0
Balance, HTM | 1 | (0)
US States and Political Subdivisions Debt Securities [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] |  |
Balance, HTM |  | 0
Corporate Debt Securities [Member] |  |
Balance, HTM | 107 | 0
Provision for credit losses, HTM | (4) | 10
Charge-offs of securities, HTM | 0 | 0
Recoveries, HTM | 0 | (37)
Balance, HTM | $ 103 | 107
Corporate Debt Securities [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] |  |
Balance, HTM |  | $ 134

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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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