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Note 4 - Securities (Details Textual) $ in Thousands | Sep. 30, 2025 USD ($) Securities | Dec. 31, 2024 USD ($)
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Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss | $ 3,320 | $ 3,170
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Securities available-for-sale, fair values | Securities available-for-sale, fair values
Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss | $ 11,889 | $ 16,506
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Securities | 534 |
Debt Securities, Available-for-Sale, Unrealized Loss Position | $ 603,882 |
Restricted Stock [Member] |  |
Restricted Investments | 3,748 | $ 1,848
National Bank of Blacksburg [Member] | Federal Home Loan Bank of Atlanta [Member] |  |
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged | $ 515,009 |

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- Definition Amount, after allowance for credit loss, of accrued interest 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 2A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-3A Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-3B + Details
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