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Note 7 - Investment and Equity Securities - Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Less than Twelve Months, Fair Value | $ 30,286 | $ 6,991
Less than Twelve Months, Gross Unrealized Losses | (355) | (12)
Twelve Months or Greater, Fair Value | 854 | 0
Twelve Months or Greater, Gross Unrealized Losses | (14) | 0
Total, Fair Value | 31,140 | 6,991
Total, Gross Unrealized Losses | (369) | (12)
Subordinated Debt Securities [Member] |  |
Less than Twelve Months, Fair Value | 6,149 | 4,243
Less than Twelve Months, Gross Unrealized Losses | (51) | (7)
Twelve Months or Greater, Fair Value | 493 | 0
Twelve Months or Greater, Gross Unrealized Losses | (7) | 0
Total, Fair Value | 6,642 | 4,243
Total, Gross Unrealized Losses | (58) | (7)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Less than Twelve Months, Fair Value | 1,674 | 2,748
Less than Twelve Months, Gross Unrealized Losses | (53) | (5)
Twelve Months or Greater, Fair Value | 361 | 0
Twelve Months or Greater, Gross Unrealized Losses | (7) | 0
Total, Fair Value | 2,035 | 2,748
Total, Gross Unrealized Losses | (60) | $ (5)
Nontaxable Municipal Bonds [Member] |  |
Less than Twelve Months, Fair Value | 22,463 |
Less than Twelve Months, Gross Unrealized Losses | (251) |
Twelve Months or Greater, Fair Value | 0 |
Twelve Months or Greater, Gross Unrealized Losses | 0 |
Total, Fair Value | 22,463 |
Total, Gross Unrealized Losses | $ (251) |

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