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Note 3 - Investments - Schedule of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Amortized cost, available for sale securities | $ 328,695 | $ 271,793 |
Gross unrealized gains, available for sale securities | 939 | 48 |
Gross unrealized losses, available for sale securities | (36,701) | (42,589) |
Fair value, available for sale securities | 292,933 | 229,252 |
Securities available for sale, AFS, ACL | 0 | 0 |
Amortized cost, held to maturity securities | 8,500 | 8,500 |
Gross unrealized gains, held to maturity securities | 0 | 0 |
Gross unrealized losses, held to maturity securities | (834) | (571) |
Securities held-to-maturity, at fair value | 7,666 | 7,929 |
Securities available for sale, HTM, ACL | 45 | 31 | $ 0
Amortized cost | 337,195 | 280,293 |
Gross unrealized gains | 939 | 48 |
Gross unrealized losses | (37,535) | (43,160) |
Total securities, fair value | 300,599 | 237,181 |
Total securities, allowance for credit loss | 45 | 31 |
US Government Agencies Debt Securities [Member] |  |  |
Amortized cost, available for sale securities | 21,151 | 21,153 |
Gross unrealized gains, available for sale securities | 46 | 0 |
Gross unrealized losses, available for sale securities | (3,179) | (3,865) |
Fair value, available for sale securities | 18,018 | 17,288 |
Securities available for sale, AFS, ACL | 0 | 0 |
Corporate Debt Securities [Member] |  |  |
Amortized cost, available for sale securities | 13,000 | 9,497 |
Gross unrealized gains, available for sale securities | 613 | 27 |
Gross unrealized losses, available for sale securities | (741) | (979) |
Fair value, available for sale securities | 12,872 | 8,545 |
Securities available for sale, AFS, ACL | 0 | 0 |
Amortized cost, held to maturity securities | 8,500 | 8,500 |
Gross unrealized gains, held to maturity securities | 0 | 0 |
Gross unrealized losses, held to maturity securities | (834) | (571) |
Securities held-to-maturity, at fair value | 7,666 | 7,929 |
Securities available for sale, HTM, ACL | 45 | 31 |
Municipal Bonds [Member] |  |  |
Amortized cost, available for sale securities | 138,803 | 144,200 |
Gross unrealized gains, available for sale securities | 42 | 21 |
Gross unrealized losses, available for sale securities | (19,398) | (23,619) |
Fair value, available for sale securities | 119,447 | 120,602 |
Securities available for sale, AFS, ACL | 0 | 0 |
Collateralized Mortgage-Backed Securities [Member] |  |  |
Amortized cost, available for sale securities | 112,855 | 82,424 |
Gross unrealized gains, available for sale securities | 238 | 0 |
Gross unrealized losses, available for sale securities | (11,845) | (12,458) |
Fair value, available for sale securities | 101,248 | 69,966 |
Securities available for sale, AFS, ACL | 0 | 0 |
U.S. Small Business Administration Securities [Member] |  |  |
Amortized cost, available for sale securities | 42,886 | 14,519 |
Gross unrealized gains, available for sale securities | 0 | 0 |
Gross unrealized losses, available for sale securities | (1,538) | (1,668) |
Fair value, available for sale securities | 41,348 | 12,851 |
Securities available for sale, AFS, ACL | $ 0 | $ 0 |

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