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Note 18 - Fair Value Disclosure Measurements - Assets Measured on a Recurring Basis (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Total debt securities | $ 164,967,000 | $ 170,199,000
Equity securities in financial institutions | 915,000 | 818,000
Investment securities available for sale, at fair value | 164,967,000 | 170,199,000
Subordinated Debt Securities [Member] |  |
Total debt securities | 30,164,000 | 32,537,000
Investment securities available for sale, at fair value | 30,164,000 | 32,537,000
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities | 7,469,000 | 10,317,000
Investment securities available for sale, at fair value | 7,469,000 | 10,317,000
Fair Value, Recurring [Member] |  |
Total debt securities | 164,967,000 | 170,199,000
Equity securities in financial institutions | 915,000 | 818,000
Total | 165,882,000 | 171,017,000
Investment securities available for sale, at fair value | 164,967,000 | 170,199,000
Fair Value, Recurring [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 30,164,000 | 32,537,000
Investment securities available for sale, at fair value | 30,164,000 | 32,537,000
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 127,334,000 | 127,345,000
Investment securities available for sale, at fair value | 127,334,000 | 127,345,000
Fair Value, Recurring [Member] | Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities | 7,469,000 | 10,317,000
Investment securities available for sale, at fair value | 7,469,000 | 10,317,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total debt securities | 0 | 0
Equity securities in financial institutions | 915,000 | 818,000
Total | 915,000 | 818,000
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 Securities, Issued by US Government Sponsored Enterprises [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 | 156,230,000 | 157,999,000
Equity securities in financial institutions | 0 | 0
Total | 156,230,000 | 157,999,000
Investment securities available for sale, at fair value | 156,230,000 | 157,999,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 21,427,000 | 20,337,000
Investment securities available for sale, at fair value | 21,427,000 | 20,337,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 127,334,000 | 127,345,000
Investment securities available for sale, at fair value | 127,334,000 | 127,345,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities | 7,469,000 | 10,317,000
Investment securities available for sale, at fair value | 7,469,000 | 10,317,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total debt securities | 8,737,000 | 12,200,000
Equity securities in financial institutions | 0 | 0
Total | 8,737,000 | 12,200,000
Investment securities available for sale, at fair value | 8,737,000 | 12,200,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 8,737,000 | 12,200,000
Investment securities available for sale, at fair value | 8,737,000 | 12,200,000
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 Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities | 0 | 0
Investment securities available for sale, at fair value | $ 0 | $ 0

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