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Note 7 - Investment and Equity Securities - Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Less than Twelve Months, Fair Value | $ 152,860 | $ 33,423
Less than Twelve Months, Gross Unrealized Losses | (21,521) | (441)
Twelve Months or Greater, Fair Value | 5,018 | 2,711
Twelve Months or Greater, Gross Unrealized Losses | (887) | (99)
Total, Fair Value | 157,878 | 36,134
Total, Gross Unrealized Losses | (22,408) | (540)
Subordinated Debt Securities [Member] |  |
Less than Twelve Months, Fair Value | 27,483 | 9,150
Less than Twelve Months, Gross Unrealized Losses | (917) | (100)
Twelve Months or Greater, Fair Value | 1,493 | 731
Twelve Months or Greater, Gross Unrealized Losses | (107) | (19)
Total, Fair Value | 28,976 | 9,881
Total, Gross Unrealized Losses | (1,024) | (119)
Nontaxable Municipal Bonds [Member] |  |
Less than Twelve Months, Fair Value | 118,890 | 24,273
Less than Twelve Months, Gross Unrealized Losses | (20,259) | (341)
Twelve Months or Greater, Fair Value | 1,847 | 0
Twelve Months or Greater, Gross Unrealized Losses | (475) | 0
Total, Fair Value | 120,737 | 24,273
Total, Gross Unrealized Losses | (20,734) | (341)
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Less than Twelve Months, Fair Value | 6,487 | 0
Less than Twelve Months, Gross Unrealized Losses | (345) | 0
Twelve Months or Greater, Fair Value | 1,678 | 1,980
Twelve Months or Greater, Gross Unrealized Losses | (305) | (80)
Total, Fair Value | 8,165 | 1,980
Total, Gross Unrealized Losses | $ (650) | $ (80)

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