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Note 6 - Investment and Equity Securities - Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Less than Twelve Months, Fair Value | $ 17,067 | $ 28,074
Less than Twelve Months, Gross Unrealized Losses | (728) | (904)
Twelve Months or Greater, Fair Value | 133,618 | 128,372
Twelve Months or Greater, Gross Unrealized Losses | (28,406) | (24,577)
Total, Fair Value | 150,685 | 156,446
Total, Gross Unrealized Losses | (29,134) | (25,481)
Subordinated Debt Securities [Member] |  |
Less than Twelve Months, Fair Value | 3,463 | 10,632
Less than Twelve Months, Gross Unrealized Losses | (37) | (368)
Twelve Months or Greater, Fair Value | 26,596 | 20,770
Twelve Months or Greater, Gross Unrealized Losses | (1,404) | (1,530)
Total, Fair Value | 30,059 | 31,402
Total, Gross Unrealized Losses | (1,441) | (1,898)
Nontaxable Municipal Bonds [Member] |  |
Less than Twelve Months, Fair Value | 12,246 | 15,456
Less than Twelve Months, Gross Unrealized Losses | (649) | (487)
Twelve Months or Greater, Fair Value | 102,212 | 102,484
Twelve Months or Greater, Gross Unrealized Losses | (26,375) | (22,318)
Total, Fair Value | 114,458 | 117,940
Total, Gross Unrealized Losses | (27,024) | (22,805)
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Less than Twelve Months, Fair Value | 1,358 | 1,986
Less than Twelve Months, Gross Unrealized Losses | (42) | (49)
Twelve Months or Greater, Fair Value | 4,810 | 5,118
Twelve Months or Greater, Gross Unrealized Losses | (627) | (729)
Total, Fair Value | 6,168 | 7,104
Total, Gross Unrealized Losses | $ (669) | $ (778)

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