Note 9 - Regulatory Matters - Schedule of Capital Amounts and Ratios (Details) $ in Thousands	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)
Total Capital (to Risk Weighted Assets)	$ 169,318	$ 165,616
Total Capital (to Risk Weighted Assets), ratio	0.1455	0.1429
Total Capital (to Risk Weighted Assets), minimum for adequacy adequacy	$ 122,171	$ 121,710
Total Capital (to Risk Weighted Assets), minimum for adequacy adequacy ratio	0.105	0.105
Total Capital (to Risk Weighted Assets), well capitalized, minimum	$ 116,353	$ 115,914
Total Capital (to Risk Weighted Assets), well capitalized, minimum ratio	0.10	0.10
Tier 1 Capital (to Risk Weighted Assets)	$ 158,199	$ 154,650
Tier 1 Capital (to Risk Weighted Assets), ratio	0.136	0.1334
Tier 1 Capital (to Risk Weighted Assets), minimum for adequacy adequacy	$ 98,900	$ 98,527
Tier 1 Capital (to Risk Weighted Assets), minimum for adequacy adequacy ratio	0.085	0.085
Tier 1 Capital (to Risk Weighted Assets), well capitalized, minimum	$ 93,082	$ 92,731
Tier 1 Capital (to Risk Weighted Assets), well capitalized, minimum ratio	0.08	0.08
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 158,199	$ 154,650
Common Equity Tier 1 Capital (to Risk Weighted Assets), ratio	0.136	0.1334
Common Equity Tier 1 Capital (to Risk Weighted Assets), minimum for adequacy adequacy	$ 81,447	$ 81,140
Common Equity Tier 1 Capital (to Risk Weighted Assets), minimum for adequacy adequacy ratio	0.07	0.07
Common Equity Tier 1 Capital (to Risk Weighted Assets), well capitalized, minimum	$ 75,629	$ 75,344
Common Equity Tier 1 Capital (to Risk Weighted Assets), well capitalized, minimum ratio	0.065	0.065
Tier 1 Capital (to Average Assets)	$ 158,199	$ 154,650
Tier 1 Capital (to Average Assets), ratio	0.0983	0.0986
Tier 1 Capital (to Average Assets), minimum for adequacy adequacy	$ 64,365	$ 62,736
Tier 1 Capital (to Average Assets), minimum for adequacy adequacy ratio	0.04	0.04
Tier 1 Capital (to Average Assets), well capitalized, minimum	$ 80,456	$ 78,420
Tier 1 Capital (to Average Assets), well capitalized, minimum ratio	0.05	0.05

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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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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

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