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Note 5 - Fair Value Measurements - Assets Measured on a Recurring Basis (Details) - USD ($) | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Total debt securities | $ 169,895,000 | $ 170,779,000
Equity securities | 895,000 | 955,000
Investment securities available for sale, at fair value | 169,895,000 | 170,779,000
Subordinated Debt Securities [Member] |  |
Total debt securities | 32,533,000 | 31,919,000
Investment securities available for sale, at fair value | 32,533,000 | 31,919,000
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Total debt securities | 7,895,000 | 6,318,000
Investment securities available for sale, at fair value | 7,895,000 | 6,318,000
Fair Value, Recurring [Member] |  |
Total debt securities | 169,895,000 | 170,779,000
Equity securities | 785,000 | 814,000
Total | 170,680,000 | 171,593,000
Investment securities available for sale, at fair value | 169,895,000 | 170,779,000
Fair Value, Recurring [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 32,533,000 | 31,919,000
Investment securities available for sale, at fair value | 32,533,000 | 31,919,000
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 129,467,000 | 132,542,000
Investment securities available for sale, at fair value | 129,467,000 | 132,542,000
Fair Value, Recurring [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Total debt securities | 7,895,000 | 6,318,000
Investment securities available for sale, at fair value | 7,895,000 | 6,318,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total debt securities | 0 | 0
Equity securities | 785,000 | 814,000
Total | 785,000 | 814,000
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 | 163,245,000 | 161,978,000
Equity securities | 0 | 0
Total | 163,245,000 | 161,978,000
Investment securities available for sale, at fair value | 163,245,000 | 161,978,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 25,883,000 | 23,118,000
Investment securities available for sale, at fair value | 25,883,000 | 23,118,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 129,467,000 | 132,542,000
Investment securities available for sale, at fair value | 129,467,000 | 132,542,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Total debt securities | 7,895,000 | 6,318,000
Investment securities available for sale, at fair value | 7,895,000 | 6,318,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total debt securities | 6,650,000 | 8,801,000
Equity securities | 0 | 0
Total | 6,650,000 | 8,801,000
Investment securities available for sale, at fair value | 6,650,000 | 8,801,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 6,650,000 | 8,801,000
Investment securities available for sale, at fair value | 6,650,000 | 8,801,000
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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