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Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) shares in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Number of Days Past Due (Day) |  | 30 days
Number of Days of Delinquent Loans Nonaccrual of Interest (Year) | 90 years |
Minimum Number of Days Consumer Loans are Past Due for Losses to be Charged Off (Day) | 120 days |
Maximum Number of Days Consumer Loans are Past Due for Losses to be Charged Off (Day) | 180 days |
Number of Days Loans Secured by Residential Or Commercial Real Estate Are Past Due for Losses to Be Carged Off (Day) | 180 days |
Period of Time Between Issuance of Loan Commitment and Closing and Sale of Loans Lower Range (Day) | 30 days |
Period of Time Between Issuance of Loan Commitments and Closing and Sale of Loans Upper Range (Day) | 60 days |
Goodwill, Impairment Loss | $ 0 | $ 0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) | 0 | 0
Advertising Expense | $ 112 | $ 99
Number of Loan Modifications for COVID-19 Related Accommodations | 0 |
National Bank of Blacksburg [Member] |  |
Noncontrolling Interest, Ownership Percentage by Parent | 100.00% |
Building [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 40 years |
Furniture and Fixtures [Member] | Minimum [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 3 years |
Furniture and Fixtures [Member] | Maximum [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 10 years |
Computer Equipment [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 3 years |

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