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Note 5 - Fair Value Measurements - Assets Measured on a Recurring Basis (Details) - USD ($) | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Total debt securities | $ 171,958,000 | $ 171,958,000 | $ 170,199,000
Equity securities in financial institutions | 779,000 |  | 818,000
Investment securities available for sale, at fair value | 171,958,000 | 171,958,000 | 170,199,000
Subordinated Debt Securities [Member] |  |  |
Total debt securities |  | 31,308,000 | 32,537,000
Investment securities available for sale, at fair value |  | 31,308,000 | 32,537,000
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |  |
Total debt securities |  | 8,342,000 | 10,317,000
Investment securities available for sale, at fair value |  | $ 8,342,000 | 10,317,000
Fair Value, Recurring [Member] |  |  |
Total debt securities | 171,958,000 |  | 170,199,000
Equity securities in financial institutions | 779,000 |  | 818,000
Total | 172,737,000 |  | 171,017,000
Investment securities available for sale, at fair value | 171,958,000 |  | 170,199,000
Fair Value, Recurring [Member] | Subordinated Debt Securities [Member] |  |  |
Total debt securities | 31,308,000 |  | 32,537,000
Investment securities available for sale, at fair value | 31,308,000 |  | 32,537,000
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] |  |  |
Total debt securities | 132,308,000 |  | 127,345,000
Investment securities available for sale, at fair value | 132,308,000 |  | 127,345,000
Fair Value, Recurring [Member] | Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |  |
Total debt securities | 8,342,000 |  | 10,317,000
Investment securities available for sale, at fair value | 8,342,000 |  | 10,317,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Total debt securities | 0 |  | 0
Equity securities in financial institutions | 779,000 |  | 818,000
Total | 779,000 |  | 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 | 162,128,000 |  | 157,999,000
Equity securities in financial institutions | 0 |  | 0
Total | 162,128,000 |  | 157,999,000
Investment securities available for sale, at fair value | 162,128,000 |  | 157,999,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Subordinated Debt Securities [Member] |  |  |
Total debt securities | 21,478,000 |  | 20,337,000
Investment securities available for sale, at fair value | 21,478,000 |  | 20,337,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |  |
Total debt securities | 132,308,000 |  | 127,345,000
Investment securities available for sale, at fair value | 132,308,000 |  | 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 | 8,342,000 |  | 10,317,000
Investment securities available for sale, at fair value | 8,342,000 |  | 10,317,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Total debt securities | 9,830,000 |  | 12,200,000
Equity securities in financial institutions | 0 |  | 0
Total | 9,830,000 |  | 12,200,000
Investment securities available for sale, at fair value | 9,830,000 |  | 12,200,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Subordinated Debt Securities [Member] |  |  |
Total debt securities | 9,830,000 |  | 12,200,000
Investment securities available for sale, at fair value | 9,830,000 |  | 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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