Note 12 - Regulatory Matters - Risk-based Capital and Related Ratios (Details) $ in Thousands	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Total capital (to risk-weighted assets), Amount	$ 189,786	$ 175,296
Total capital (to risk-weighted assets), Ratio	0.1345	0.1266
Total capital (to risk-weighted assets), Minimum required for capital adequacy purposes	0.08	0.08
Total capital (to risk-weighted assets), Minimum required for capital adequacy purposes with conservation buffer	0.105	0.105
Total capital (to risk-weighted assets), To be well capitalized under prompt corrective action	0.10	0.10
Tier I capital (to risk-weighted assets), Amount	$ 176,172	$ 161,896
Tier I capital (to risk-weighted assets), Ratio	0.1249	0.1169
Tier I capital (to risk-weighted assets), Minimum required for capital adequacy purposes	0.06	0.06
Tier I capital (to risk-weighted assets), Minimum required for capital adequacy purposes with conservation buffer	0.085	0.085
Tier I capital (to risk-weighted assets), To be well capitalized under prompt corrective action	0.08	0.08
Tier I common equity (to risk-weighted assets), Amount	$ 176,172	$ 161,896
Tier I common equity (to risk-weighted assets), Ratio	0.1249	0.1169
Tier I common equity (to risk-weighted assets), Minimum required for capital adequacy purposes	0.045	0.045
Tier I common equity (to risk-weighted assets), Minimum required for capital adequacy purposes with conservation buffer	0.07	0.07
Tier I common equity (to risk-weighted assets), To be well capitalized under prompt corrective action	0.065	0.065
Tier I capital (to average assets), Amount	$ 176,172	$ 161,896
Tier I capital (to average assets), Ratio	0.0947	0.0876
Tier I capital (to average assets), Minimum required for capital adequacy purposes	0.04	0.04
Tier I capital (to average assets), Minimum required for capital adequacy purposes with conservation buffer	0.04	0.04
Tier I capital (to average assets), To be well capitalized under prompt corrective action	0.05	0.05
Total risk-weighted assets, Amount	$ 1,410,755	$ 1,384,710
Total average assets, Amount	$ 1,861,189	$ 1,848,752

Amount of average assets as calculated in accordance with U.S. Federal regulatory capital standards.

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The minimum total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action, plus the capital conservation buffer (phased in at 0.625% annually).

+ References

No definition available.

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The minimum Common Equity Tier One Capital Ratio (Common Equity Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action, plus the fully phased-in capital conservation buffer (phased in at 0.625% annually).

+ References

No definition available.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations, plus the capital conservation buffer (phased in at 0.625% annually).

+ References

No definition available.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action, plus the fully phased in capital conservation buffer (phased in at 0.625% annually).

+ References

No definition available.

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Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Amount of total capital as defined by regulatory framework.

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Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Amount of Common Equity Tier 1 risk-based capital as defined by regulatory framework.

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Amount of risk-weighted assets as defined by regulatory framework.

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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