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Note 4 - Securities (Details Textual) $ in Thousands | Mar. 31, 2025 USD ($) Securities | Dec. 31, 2024 USD ($)
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Debt Securities, Available-for-Sale, Allowance for Credit Losses | $ 0 | $ 0
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss | $ 3,289 | $ 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 | $ 14,488 | $ 16,506
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Securities | 545 |
Debt Securities, Available-for-Sale, Unrealized Loss Position | $ 571,226 |
Restricted Stock [Member] |  |
Restricted Investments | 1,848 | $ 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 | $ 517,038 |

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