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Note 6 - Investment and Equity Securities - Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Less than Twelve Months, Fair Value | $ 1,753 | $ 28,074
Less than Twelve Months, Gross Unrealized Losses | (26) | (904)
Twelve Months or Greater, Fair Value | 136,838 | 128,372
Twelve Months or Greater, Gross Unrealized Losses | (24,017) | (24,577)
Total, Fair Value | 138,590 | 156,446
Total, Gross Unrealized Losses | (24,044) | (25,481)
Subordinated Debt Securities [Member] |  |
Less than Twelve Months, Fair Value | 727 | 10,632
Less than Twelve Months, Gross Unrealized Losses | (23) | (368)
Twelve Months or Greater, Fair Value | 19,761 | 20,770
Twelve Months or Greater, Gross Unrealized Losses | (989) | (1,530)
Total, Fair Value | 20,487 | 31,402
Total, Gross Unrealized Losses | (1,013) | (1,898)
Nontaxable Municipal Bonds [Member] |  |
Less than Twelve Months, Fair Value | 0 | 15,456
Less than Twelve Months, Gross Unrealized Losses | 0 | (487)
Twelve Months or Greater, Fair Value | 111,984 | 102,484
Twelve Months or Greater, Gross Unrealized Losses | (22,499) | (22,318)
Total, Fair Value | 111,984 | 117,940
Total, Gross Unrealized Losses | (22,499) | (22,805)
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Less than Twelve Months, Fair Value | 1,026 | 1,986
Less than Twelve Months, Gross Unrealized Losses | (3) | (49)
Twelve Months or Greater, Fair Value | 5,093 | 5,118
Twelve Months or Greater, Gross Unrealized Losses | (529) | (729)
Total, Fair Value | 6,119 | 7,104
Total, Gross Unrealized Losses | $ (532) | $ (778)

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