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Note 3 - Securities (Details Textual) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Number of Temporarily Impaired Securities | 291 |
Available-for-sale and Held to Maturity Securities Continuous Unrealized Loss Position Fair Value | $ 318,413 |
Continuous Unrealized Loss Position Aggregate Losses | $ 7,067 |
Number of Temporarily Impaired Securities Greater than Twelve Months | 48 |
Continuous Unrealized Loss Position Twelve Months or Longer Fair Value | $ 51,999 | $ 4,695
Continuous Unrealized Loss Position 12 Months or Longer Aggregate Losses | 2,145 | 5
Debt Securities, Available-for-sale, Restricted | 287,023 | 251,048
Debt Securities, Available-for-sale, Realized Gain |  | 108
National Bank of Blacksburg [Member] | Federal Home Loan Bank of Atlanta [Member] |  |
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged | 603,827 |
Restricted Stock [Member] |  |
Restricted Investments | $ 845 | 1,279
US Government Agencies Debt Securities [Member] |  |
Number of Temporarily Impaired Securities | 28 |
Available-for-sale and Held to Maturity Securities Continuous Unrealized Loss Position Fair Value | $ 26,792 |
Continuous Unrealized Loss Position Aggregate Losses | 1,180 |
Continuous Unrealized Loss Position Twelve Months or Longer Fair Value | 26,792 | 0
Continuous Unrealized Loss Position 12 Months or Longer Aggregate Losses | $ 1,180 | 0
US States and Political Subdivisions Debt Securities [Member] |  |
Number of Temporarily Impaired Securities | 17 |
Available-for-sale and Held to Maturity Securities Continuous Unrealized Loss Position Fair Value | $ 20,542 |
Continuous Unrealized Loss Position Aggregate Losses | 793 |
Continuous Unrealized Loss Position Twelve Months or Longer Fair Value | 20,542 | 635
Continuous Unrealized Loss Position 12 Months or Longer Aggregate Losses | $ 793 | 3
Collateralized Mortgage Backed Securities [Member] |  |
Number of Temporarily Impaired Securities | 3 |
Available-for-sale and Held to Maturity Securities Continuous Unrealized Loss Position Fair Value | $ 4,665 |
Continuous Unrealized Loss Position Aggregate Losses | 172 |
Securities Called [Member] |  |
Debt Securities, Available-for-sale, Realized Gain (Loss), Total | $ 6 |
Debt Securities, Available-for-sale, Realized Gain |  | 65
Securities Sold [Member] |  |
Debt Securities, Available-for-sale, Realized Gain |  | $ 43

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