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Note 3 - Securities (Details Textual) Pure in Thousands, $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2023 USD ($)
Debt Securities, Available-for-Sale, Allowance for Credit Loss | $ 0 |  | $ 0
Interest Receivable on Securities | 3,444 |  | 3,281
Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss | $ 17,516 |  | $ 16,629
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | 574 |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position | $ 598,720 |  |
Debt Securities, Available-for-Sale, Realized Gain (Loss) | (0) | $ 12 |
Available-for-sale Securities Sold, Book Value |  | $ 17,987 |
National Bank of Blacksburg [Member] | Federal Home Loan Bank of Atlanta [Member] |  |  |
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged | $ 506,896 |  |

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