Note 3 - Securities (Details Textual) Pure in Thousands, $ in Thousands	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Interest Receivable on Securities	$ 3,420	$ 3,485
Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss	$ 23,211	$ 21,644
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	577
Debt Securities, Available-for-Sale, Unrealized Loss Position	$ 591,307
National Bank of Blacksburg [Member] \| Federal Home Loan Bank of Atlanta [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 510,786

The amount of interest receivable on securities

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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