v3.26.1
Note 3 - Securities (Details Textual)
12 Months Ended
Dec. 31, 2025
USD ($)
Securities
Dec. 31, 2024
USD ($)
Marketable Securities [Line Items]    
Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss $ 10,889,000 $ 16,506,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Securities 522  
Debt Securities, Available-for-Sale, Unrealized Loss Position $ 601,783,000  
Proceeds from Sale of Debt Securities, Available for Sale 0  
Debt Securities, Available-for-Sale, Restricted 654,370,000 536,260,000
National Bank of Blacksburg [Member] | Federal Home Loan Bank of Atlanta [Member]    
Marketable Securities [Line Items]    
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged 517,382,000  
Restricted Stock [Member]    
Marketable Securities [Line Items]    
Restricted Investments $ 1,848,000 1,848,000
Securities Called [Member]    
Marketable Securities [Line Items]    
Debt Securities, Available-for-Sale, Realized Gain (Loss)   $ 0