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Note 3 - Securities (Details Textual) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 USD ($) Securities | Dec. 31, 2023 USD ($)
Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss | $ 16,506 | $ 16,629
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Securities | 564 |
Debt Securities, Available-for-Sale, Unrealized Loss Position | $ 583,947 |
Debt Securities, Available-for-Sale, Realized Gain (Loss) | 0 | (3,332)
Debt Securities, Available-for-Sale, Restricted | 536,260 | 534,465
National Bank of Blacksburg [Member] | Federal Home Loan Bank of Atlanta [Member] |  |
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged | 515,921 |
Restricted Stock [Member] |  |
Restricted Investments | 1,848 | 1,264
Securities Called [Member] |  |
Debt Securities, Available-for-Sale, Realized Gain (Loss) | $ 0 | $ 3,332

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- Definition Amount of realized gain (loss) 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/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-9 + Details
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- Definition Amount of restricted 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 860 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 954 -SubTopic 210 -Name Accounting Standards Codification -Section 45 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477220/954-210-45-4 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 954 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478600/954-210-50-2 + Details
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