Note 3 - Securities (Details Textual) $ in Thousands	3 Months Ended
Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss	$ 19,112		$ 21,644
Number of Temporarily Impaired Securities Greater than Twelve Months	578
Continuous Unrealized Loss Position Aggregate Losses	$ 613,836
Available-for-sale Securities Sold, Book Value	28,863	$ 17,987
Realized Investment Gains (Losses)	(3,344)	$ 12
National Bank of Blacksburg [Member] \| Federal Home Loan Bank of Atlanta [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 633,617

Represents the book value of available-for-sale securities that had been sold.

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Amount of the excess of amortized cost basis over fair value of securities that are in a loss position.

+ References

No definition available.

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This item contains disclosure of the number of investment positions determined to be temporarily impaired in a continuous loss position for twelve months or more.

+ References

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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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-6

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
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- Definition

Amount of realized gain (loss) on investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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