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Note 4 - Investment and Equity Securities - Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Less than Twelve Months, Fair Value | $ 33,423 | $ 6,991
Less than Twelve Months, Gross Unrealized Losses | (441) | (12)
Twelve Months or Greater, Fair Value | 2,711 | 0
Twelve Months or Greater, Gross Unrealized Losses | (99) | 0
Total, Fair Value | 36,134 | 6,991
Total, Gross Unrealized Losses | (540) | (12)
Subordinated Debt Securities [Member] |  |
Less than Twelve Months, Fair Value | 9,150 | 4,243
Less than Twelve Months, Gross Unrealized Losses | (100) | (7)
Twelve Months or Greater, Fair Value | 731 | 0
Twelve Months or Greater, Gross Unrealized Losses | (19) | 0
Total, Fair Value | 9,881 | 4,243
Total, Gross Unrealized Losses | (119) | (7)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Less than Twelve Months, Fair Value | 0 | 2,748
Less than Twelve Months, Gross Unrealized Losses | 0 | (5)
Twelve Months or Greater, Fair Value | 1,980 | 0
Twelve Months or Greater, Gross Unrealized Losses | (80) | 0
Total, Fair Value | 1,980 | 2,748
Total, Gross Unrealized Losses | (80) | $ (5)
Nontaxable Municipal Bonds [Member] |  |
Less than Twelve Months, Fair Value | 24,273 |
Less than Twelve Months, Gross Unrealized Losses | (341) |
Twelve Months or Greater, Fair Value | 0 |
Twelve Months or Greater, Gross Unrealized Losses | 0 |
Total, Fair Value | 24,273 |
Total, Gross Unrealized Losses | $ (341) |

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