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Note 5 - Fair Value Measurements - Assets Measured on a Recurring Basis (Details) - USD ($) | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Total debt securities | $ 165,014,000 | $ 165,802,000
Equity securities | 1,021,000 | 855,000
Investment securities available for sale, at fair value | 165,014,000 | 165,802,000
Subordinated Debt Securities [Member] |  |
Total debt securities | 32,829,000 | 32,469,000
Investment securities available for sale, at fair value | 32,829,000 | 32,469,000
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Total debt securities | 8,334,000 | 8,367,000
Investment securities available for sale, at fair value | 8,334,000 | 8,367,000
Fair Value, Recurring [Member] |  |
Total debt securities | 165,014,000 | 165,802,000
Equity securities | 728,000 | 753,000
Total | 165,742,000 | 166,555,000
Investment securities available for sale, at fair value | 165,014,000 | 165,802,000
Fair Value, Recurring [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 32,829,000 | 32,469,000
Investment securities available for sale, at fair value | 32,829,000 | 32,469,000
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 123,851,000 | 124,966,000
Investment securities available for sale, at fair value | 123,851,000 | 124,966,000
Fair Value, Recurring [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Total debt securities | 8,334,000 | 8,367,000
Investment securities available for sale, at fair value | 8,334,000 | 8,367,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total debt securities | 0 | 0
Equity securities | 728,000 | 753,000
Total | 728,000 | 753,000
Investment securities available for sale, at fair value | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 0 | 0
Investment securities available for sale, at fair value | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 0 | 0
Investment securities available for sale, at fair value | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Total debt securities | 0 | 0
Investment securities available for sale, at fair value | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Total debt securities | 158,360,000 | 159,163,000
Equity securities | 0 | 0
Total | 158,360,000 | 159,163,000
Investment securities available for sale, at fair value | 158,360,000 | 159,163,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 26,175,000 | 25,830,000
Investment securities available for sale, at fair value | 26,175,000 | 25,830,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 123,851,000 | 124,966,000
Investment securities available for sale, at fair value | 123,851,000 | 124,966,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Total debt securities | 8,334,000 | 8,367,000
Investment securities available for sale, at fair value | 8,334,000 | 8,367,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total debt securities | 6,654,000 | 6,639,000
Equity securities | 0 | 0
Total | 6,654,000 | 6,639,000
Investment securities available for sale, at fair value | 6,654,000 | 6,639,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 6,654,000 | 6,639,000
Investment securities available for sale, at fair value | 6,654,000 | 6,639,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 0 | 0
Investment securities available for sale, at fair value | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Total debt securities | 0 | 0
Investment securities available for sale, at fair value | $ 0 | $ 0

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