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Note 3 - Investments - Schedule of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | ---
Amortized cost, available for sale securities | $ 310,272 | $ 328,695 |  |
Gross unrealized gains, available for sale securities | 471 | 939 |  |
Gross unrealized losses, available for sale securities | (29,568) | (36,701) |  |
Total securities available-for-sale, fair value | 281,175 | 292,933 |  |
Available-for-Sale, Allowance for Credit Loss | 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 | (356) | (834) |  |
Securities held-to-maturity, at fair value | 8,144 | 7,666 |  |
Securities available for sale, HTM, ACL | 45 | 45 | $ 31 | $ 0
Amortized cost, available for sale and held to maturity securities | 318,772 | 337,195 |  |
Gross unrealized gains, available for sale and held to maturity securities | 471 | 939 |  |
Gross unrealized losses, available for sale and held to maturity securities | (29,924) | (37,535) |  |
Total securities, fair value | 289,319 | 300,599 |  |
ACL, available for sale and held to maturity securities | 45 | 45 |  |
US Government Agencies Debt Securities [Member] |  |  |  |
Amortized cost, available for sale securities | 20,247 | 21,151 |  |
Gross unrealized gains, available for sale securities | 45 | 46 |  |
Gross unrealized losses, available for sale securities | (3,154) | (3,179) |  |
Total securities available-for-sale, fair value | 17,138 | 18,018 |  |
Available-for-Sale, Allowance for Credit Loss | 0 | 0 |  |
Corporate Debt Securities [Member] |  |  |  |
Amortized cost, available for sale securities | 16,000 | 13,000 |  |
Gross unrealized gains, available for sale securities | 8 | 613 |  |
Gross unrealized losses, available for sale securities | (882) | (741) |  |
Total securities available-for-sale, fair value | 15,126 | 12,872 |  |
Available-for-Sale, Allowance for Credit Loss | 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 | (356) | (834) |  |
Securities held-to-maturity, at fair value | 8,144 | 7,666 |  |
Securities available for sale, HTM, ACL | 45 | 45 |  |
Municipal Bonds [Member] |  |  |  |
Amortized cost, available for sale securities | 82,774 | 138,803 |  |
Gross unrealized gains, available for sale securities | 0 | 42 |  |
Gross unrealized losses, available for sale securities | (12,430) | (19,398) |  |
Total securities available-for-sale, fair value | 70,344 | 119,447 |  |
Available-for-Sale, Allowance for Credit Loss | 0 | 0 |  |
Collateralized Mortgage-Backed Securities [Member] |  |  |  |
Amortized cost, available for sale securities | 178,740 | 112,855 |  |
Gross unrealized gains, available for sale securities | 415 | 238 |  |
Gross unrealized losses, available for sale securities | (11,969) | (11,845) |  |
Total securities available-for-sale, fair value | 167,186 | 101,248 |  |
Available-for-Sale, Allowance for Credit Loss | 0 | 0 |  |
Asset-Backed Securities [Member] |  |  |  |
Amortized cost, available for sale securities | 12,511 | 42,886 |  |
Gross unrealized gains, available for sale securities | 3 | 0 |  |
Gross unrealized losses, available for sale securities | (1,133) | (1,538) |  |
Total securities available-for-sale, fair value | 11,381 | 41,348 |  |
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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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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