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Note 2 - Investments - Schedule of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Jun. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | --- | --- | --- | --- | ---
Amortized cost, available for sale securities | $ 335,152 |  | $ 310,272 |  |  |
Gross unrealized gains, available for sale securities | 908 |  | 471 |  |  |
Gross unrealized losses, available for sale securities | (24,365) |  | (29,568) |  |  |
Total securities available-for-sale, fair value | 311,695 |  | 281,175 |  |  |
Available-for-Sale, Allowance for Credit Loss | 0 |  | 0 |  |  |
Amortized cost, held to maturity securities | 31,606 |  | 8,500 |  |  |
Gross unrealized gains, held to maturity securities | 618 |  | 0 |  |  |
Gross unrealized losses, held to maturity securities | (82) |  | (356) |  |  |
Securities held-to-maturity, at fair value | 32,142 |  | 8,144 |  |  |
Securities held-to-maturity, ACL | 220 | $ 220 | 45 | $ 45 | $ 45 | $ 45
Amortized cost, available for sale and held to maturity securities | 366,758 |  | 318,772 |  |  |
Gross unrealized gains, available for sale and held to maturity securities | 1,526 |  | 471 |  |  |
Gross unrealized losses, available for sale and held to maturity securities | (24,447) |  | (29,924) |  |  |
Total securities, fair value | 343,837 |  | 289,319 |  |  |
ACL, available for sale and held to maturity securities | 220 |  | 45 |  |  |
US Government Agencies Debt Securities [Member] |  |  |  |  |  |
Amortized cost, available for sale securities | 20,260 |  | 20,247 |  |  |
Gross unrealized gains, available for sale securities | 31 |  | 45 |  |  |
Gross unrealized losses, available for sale securities | (2,303) |  | (3,154) |  |  |
Total securities available-for-sale, fair value | 17,988 |  | 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 | 7 |  | 8 |  |  |
Gross unrealized losses, available for sale securities | (556) |  | (882) |  |  |
Total securities available-for-sale, fair value | 15,451 |  | 15,126 |  |  |
Available-for-Sale, Allowance for Credit Loss | 0 |  | 0 |  |  |
Amortized cost, held to maturity securities | 29,336 |  | 8,500 |  |  |
Gross unrealized gains, held to maturity securities | 404 |  | 0 |  |  |
Gross unrealized losses, held to maturity securities | (82) |  | (356) |  |  |
Securities held-to-maturity, at fair value | 29,658 |  | 8,144 |  |  |
Securities held-to-maturity, ACL | 220 |  | 45 |  |  |
Municipal Bonds [Member] |  |  |  |  |  |
Amortized cost, available for sale securities | 81,925 |  | 82,774 |  |  |
Gross unrealized gains, available for sale securities | 5 |  | 0 |  |  |
Gross unrealized losses, available for sale securities | (11,225) |  | (12,430) |  |  |
Total securities available-for-sale, fair value | 70,705 |  | 70,344 |  |  |
Available-for-Sale, Allowance for Credit Loss | 0 |  | 0 |  |  |
Amortized cost, held to maturity securities | 2,270 |  |  |  |  |
Gross unrealized gains, held to maturity securities | 214 |  |  |  |  |
Gross unrealized losses, held to maturity securities | 0 |  |  |  |  |
Securities held-to-maturity, at fair value | 2,484 |  |  |  |  |
Securities held-to-maturity, ACL | 0 |  |  |  |  |
Collateralized Mortgage-Backed Securities [Member] |  |  |  |  |  |
Amortized cost, available for sale securities | 205,937 |  | 178,740 |  |  |
Gross unrealized gains, available for sale securities | 865 |  | 415 |  |  |
Gross unrealized losses, available for sale securities | (9,580) |  | (11,969) |  |  |
Total securities available-for-sale, fair value | 197,222 |  | 167,186 |  |  |
Available-for-Sale, Allowance for Credit Loss | 0 |  | 0 |  |  |
Asset-Backed Securities [Member] |  |  |  |  |  |
Amortized cost, available for sale securities | 11,030 |  | 12,511 |  |  |
Gross unrealized gains, available for sale securities | 0 |  | 3 |  |  |
Gross unrealized losses, available for sale securities | (701) |  | (1,133) |  |  |
Total securities available-for-sale, fair value | 10,329 |  | 11,381 |  |  |
Available-for-Sale, Allowance for Credit Loss | $ 0 |  | $ 0 |  |  |

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