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Note 5 - Fair Value Measurements - Assets Measured on a Recurring Basis (Details) - USD ($)	Sep. 30, 2025	Dec. 31, 2024
Total debt securities	$ 155,855,000	$ 165,802,000
Equity securities	1,131,000	855,000
Investment securities available for sale, at fair value	155,855,000	165,802,000
Subordinated Debt Securities [Member]
Total debt securities	23,572,000	32,469,000
Investment securities available for sale, at fair value	23,572,000	32,469,000
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Total debt securities	7,910,000	8,367,000
Investment securities available for sale, at fair value	7,910,000	8,367,000
Fair Value, Recurring [Member]
Total debt securities	155,855,000	165,802,000
Equity securities	743,000	753,000
Interest rate derivative assets	547,000
Interest rate derivative liabilities	547,000
Investment securities available for sale, at fair value	155,855,000	165,802,000
Fair Value, Recurring [Member] | Subordinated Debt Securities [Member]
Total debt securities	23,572,000	32,469,000
Investment securities available for sale, at fair value	23,572,000	32,469,000
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member]
Total debt securities	124,373,000	124,966,000
Investment securities available for sale, at fair value	124,373,000	124,966,000
Fair Value, Recurring [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Total debt securities	7,910,000	8,367,000
Investment securities available for sale, at fair value	7,910,000	8,367,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total debt securities	0	0
Equity securities	743,000	753,000
Interest rate derivative assets
Interest rate derivative liabilities
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	154,176,000	159,163,000
Equity securities	0	0
Interest rate derivative assets	547,000
Interest rate derivative liabilities	547,000
Investment securities available for sale, at fair value	154,176,000	159,163,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Subordinated Debt Securities [Member]
Total debt securities	21,893,000	25,830,000
Investment securities available for sale, at fair value	21,893,000	25,830,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member]
Total debt securities	124,373,000	124,966,000
Investment securities available for sale, at fair value	124,373,000	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	7,910,000	8,367,000
Investment securities available for sale, at fair value	7,910,000	8,367,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Total debt securities	1,679,000	6,639,000
Equity securities	0	0
Interest rate derivative assets
Interest rate derivative liabilities
Investment securities available for sale, at fair value	1,679,000	6,639,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Subordinated Debt Securities [Member]
Total debt securities	1,679,000	6,639,000
Investment securities available for sale, at fair value	1,679,000	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

X

- Definition

Amount excluding accrued interest, of 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/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482736/825-10-45-1A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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