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Note 2 - Securities - Unrealized Gross Losses and Fair Value of Securities in a Continuous Loss Position (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Securities available for sale, gross unrealized losses, less than twelve months | $ (229) | $ (176)
Securities available for sale, fair value, less than twelve months | 24,200 | 19,494
Securities available for sale, gross unrealized losses, twelve months or longer | (30,209) | (38,151)
Securities available for sale, fair value, twelve months or longer | 242,113 | 274,306
Securities available for sale, gross unrealized losses, total | (30,438) | (38,327)
Securities available for sale, fair value, total | 266,313 | 293,800
US States and Political Subdivisions Debt Securities [Member] |  |
Securities available for sale, gross unrealized losses, less than twelve months | 0 | 0
Securities available for sale, fair value, less than twelve months | 0 | 0
Securities available for sale, gross unrealized losses, twelve months or longer | (12,210) | (15,237)
Securities available for sale, fair value, twelve months or longer | 81,363 | 87,461
Securities available for sale, gross unrealized losses, total | (12,210) | (15,237)
Securities available for sale, fair value, total | 81,363 | 87,461
US Government Agencies Debt Securities [Member] |  |
Securities available for sale, gross unrealized losses, less than twelve months | (32) | (65)
Securities available for sale, fair value, less than twelve months | 9,520 | 11,782
Securities available for sale, gross unrealized losses, twelve months or longer | 0 | 0
Securities available for sale, fair value, twelve months or longer | 0 | 0
Securities available for sale, gross unrealized losses, total | (32) | (65)
Securities available for sale, fair value, total | 9,520 | 11,782
Corporate Issued Asset-backed Securities [Member] |  |
Securities available for sale, gross unrealized losses, less than twelve months | (21) | (84)
Securities available for sale, fair value, less than twelve months | 4,815 | 3,771
Securities available for sale, gross unrealized losses, twelve months or longer | 0 | 0
Securities available for sale, fair value, twelve months or longer | 0 | 0
Securities available for sale, gross unrealized losses, total | (21) | (84)
Securities available for sale, fair value, total | 4,815 | 3,771
Corporate Debt Securities [Member] |  |
Securities available for sale, gross unrealized losses, less than twelve months | (50) | 0
Securities available for sale, fair value, less than twelve months | 1,640 | 0
Securities available for sale, gross unrealized losses, twelve months or longer | (4,023) | (5,061)
Securities available for sale, fair value, twelve months or longer | 52,418 | 51,454
Securities available for sale, gross unrealized losses, total | (4,073) | (5,061)
Securities available for sale, fair value, total | 54,058 | 51,454
US Small Business Administration Securities [Member] |  |
Securities available for sale, gross unrealized losses, less than twelve months | (7) |
Securities available for sale, fair value, less than twelve months | 983 |
Securities available for sale, gross unrealized losses, twelve months or longer | 0 |
Securities available for sale, fair value, twelve months or longer | 0 |
Securities available for sale, gross unrealized losses, total | (7) |
Securities available for sale, fair value, total | 983 |
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Securities available for sale, gross unrealized losses, less than twelve months | (119) | (27)
Securities available for sale, fair value, less than twelve months | 7,242 | 3,941
Securities available for sale, gross unrealized losses, twelve months or longer | (10,321) | (12,391)
Securities available for sale, fair value, twelve months or longer | 51,487 | 59,305
Securities available for sale, gross unrealized losses, total | (10,440) | (12,418)
Securities available for sale, fair value, total | 58,729 | 63,246
Mortgage-Backed Securities, Issued by Private Enterprises [Member] |  |
Securities available for sale, gross unrealized losses, less than twelve months | 0 | 0
Securities available for sale, fair value, less than twelve months | 0 | 0
Securities available for sale, gross unrealized losses, twelve months or longer | (3,655) | (5,462)
Securities available for sale, fair value, twelve months or longer | 56,845 | 76,086
Securities available for sale, gross unrealized losses, total | (3,655) | (5,462)
Securities available for sale, fair value, total | $ 56,845 | $ 76,086

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