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Note 6 - Investment and Equity Securities - Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Less than Twelve Months, Fair Value | $ 28,074 | $ 2,575
Less than Twelve Months, Gross Unrealized Losses | (904) | (17)
Twelve Months or Greater, Fair Value | 128,372 | 141,556
Twelve Months or Greater, Gross Unrealized Losses | (24,577) | (20,573)
Total, Fair Value | 156,446 | 144,131
Total, Gross Unrealized Losses | (25,481) | (20,590)
Subordinated Debt Securities [Member] |  |
Less than Twelve Months, Fair Value | 10,632 | 994
Less than Twelve Months, Gross Unrealized Losses | (368) | (6)
Twelve Months or Greater, Fair Value | 20,770 | 29,356
Twelve Months or Greater, Gross Unrealized Losses | (1,530) | (2,445)
Total, Fair Value | 31,402 | 30,350
Total, Gross Unrealized Losses | (1,898) | (2,451)
Nontaxable Municipal Bonds [Member] |  |
Less than Twelve Months, Fair Value | 15,456 | 1,386
Less than Twelve Months, Gross Unrealized Losses | (487) | (10)
Twelve Months or Greater, Fair Value | 102,484 | 106,078
Twelve Months or Greater, Gross Unrealized Losses | (22,318) | (17,482)
Total, Fair Value | 117,940 | 107,464
Total, Gross Unrealized Losses | (22,805) | (17,492)
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Less than Twelve Months, Fair Value | 1,986 | 195
Less than Twelve Months, Gross Unrealized Losses | (49) | (1)
Twelve Months or Greater, Fair Value | 5,118 | 6,122
Twelve Months or Greater, Gross Unrealized Losses | (729) | (646)
Total, Fair Value | 7,104 | 6,317
Total, Gross Unrealized Losses | $ (778) | $ (647)

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