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Note 2 - Investments - Schedule of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024 | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | --- | --- | ---
Amortized cost, available for sale securities | $ 316,735 | $ 310,272 |  |
Gross unrealized gains, available for sale securities | 1,582 | 471 |  |
Gross unrealized losses, available for sale securities | (27,184) | (29,568) |  |
Total securities available-for-sale, fair value | 291,133 | 281,175 |  |
Available-for-Sale, Allowance for Credit Loss | 0 | 0 |  |
Amortized cost, held to maturity securities | 10,500 | 8,500 |  |
Gross unrealized gains, held to maturity securities | 1 | 0 |  |
Gross unrealized losses, held to maturity securities | (243) | (356) |  |
Securities held-to-maturity, at fair value | 10,258 | 8,144 |  |
Securities held-to-maturity | 66 | 45 | $ 45 | $ 45
Amortized cost, available for sale and held to maturity securities | 327,235 | 318,772 |  |
Gross unrealized gains, available for sale and held to maturity securities | 1,583 | 471 |  |
Gross unrealized losses, available for sale and held to maturity securities | (27,427) | (29,924) |  |
Total securities, fair value | 301,391 | 289,319 |  |
ACL, available for sale and held to maturity securities | 66 | 45 |  |
US Government Agencies Debt Securities [Member] |  |  |  |
Amortized cost, available for sale securities | 20,251 | 20,247 |  |
Gross unrealized gains, available for sale securities | 45 | 45 |  |
Gross unrealized losses, available for sale securities | (2,728) | (3,154) |  |
Total securities available-for-sale, fair value | 17,568 | 17,138 |  |
Available-for-Sale, Allowance for Credit Loss | 0 | 0 |  |
Corporate Debt Securities [Member] |  |  |  |
Amortized cost, available for sale securities | 16,000 | 16,000 |  |
Gross unrealized gains, available for sale securities | 8 | 8 |  |
Gross unrealized losses, available for sale securities | (821) | (882) |  |
Total securities available-for-sale, fair value | 15,187 | 15,126 |  |
Available-for-Sale, Allowance for Credit Loss | 0 | 0 |  |
Amortized cost, held to maturity securities | 10,500 | 8,500 |  |
Gross unrealized gains, held to maturity securities | 1 | 0 |  |
Gross unrealized losses, held to maturity securities | (243) | (356) |  |
Securities held-to-maturity, at fair value | 10,258 | 8,144 |  |
Securities held-to-maturity | 66 | 45 |  |
Municipal Bonds [Member] |  |  |  |
Amortized cost, available for sale securities | 82,495 | 82,774 |  |
Gross unrealized gains, available for sale securities | 0 | 0 |  |
Gross unrealized losses, available for sale securities | (12,374) | (12,430) |  |
Total securities available-for-sale, fair value | 70,121 | 70,344 |  |
Available-for-Sale, Allowance for Credit Loss | 0 | 0 |  |
Collateralized Mortgage-Backed Securities [Member] |  |  |  |
Amortized cost, available for sale securities | 186,222 | 178,740 |  |
Gross unrealized gains, available for sale securities | 1,462 | 415 |  |
Gross unrealized losses, available for sale securities | (10,302) | (11,969) |  |
Total securities available-for-sale, fair value | 177,382 | 167,186 |  |
Available-for-Sale, Allowance for Credit Loss | 0 | 0 |  |
Asset-Backed Securities [Member] |  |  |  |
Amortized cost, available for sale securities | 11,767 | 12,511 |  |
Gross unrealized gains, available for sale securities | 67 | 3 |  |
Gross unrealized losses, available for sale securities | (959) | (1,133) |  |
Total securities available-for-sale, fair value | 10,875 | 11,381 |  |
Available-for-Sale, Allowance for Credit Loss | $ 0 | $ 0 |  |

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- Definition Amount of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) excluding accrued interest. + References No definition available. + Details
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