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Note 5 - Fair Value Measurements - Assets Measured on a Recurring Basis (Details) - USD ($)	Jun. 30, 2025	Dec. 31, 2024
Total debt securities	$ 161,116,000	$ 165,802,000
Equity securities	1,014,000	855,000
Investment securities available for sale, at fair value	161,116,000	165,802,000
Subordinated Debt Securities [Member]
Total debt securities	32,634,000	32,469,000
Investment securities available for sale, at fair value	32,634,000	32,469,000
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Total debt securities	8,000,000	8,367,000
Investment securities available for sale, at fair value	8,000,000	8,367,000
Fair Value, Recurring [Member]
Total debt securities	161,116,000	165,802,000
Equity securities	729,000	753,000
Total	161,845,000	166,555,000
Investment securities available for sale, at fair value	161,116,000	165,802,000
Fair Value, Recurring [Member] | Subordinated Debt Securities [Member]
Total debt securities	32,634,000	32,469,000
Investment securities available for sale, at fair value	32,634,000	32,469,000
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member]
Total debt securities	120,482,000	124,966,000
Investment securities available for sale, at fair value	120,482,000	124,966,000
Fair Value, Recurring [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Total debt securities	8,000,000	8,367,000
Investment securities available for sale, at fair value	8,000,000	8,367,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total debt securities	0	0
Equity securities	729,000	753,000
Total	729,000	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	154,457,000	159,163,000
Equity securities	0	0
Total	154,457,000	159,163,000
Investment securities available for sale, at fair value	154,457,000	159,163,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Subordinated Debt Securities [Member]
Total debt securities	25,975,000	25,830,000
Investment securities available for sale, at fair value	25,975,000	25,830,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member]
Total debt securities	120,482,000	124,966,000
Investment securities available for sale, at fair value	120,482,000	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	8,000,000	8,367,000
Investment securities available for sale, at fair value	8,000,000	8,367,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Total debt securities	6,659,000	6,639,000
Equity securities	0	0
Total	6,659,000	6,639,000
Investment securities available for sale, at fair value	6,659,000	6,639,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Subordinated Debt Securities [Member]
Total debt securities	6,659,000	6,639,000
Investment securities available for sale, at fair value	6,659,000	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
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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

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-Topic 210
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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