Note 12 - Regulatory Matters - Capital Amounts and Ratios (Details) $ in Thousands	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Tier 1 (Core) Capital to average total assets Bank, actual amount	$ 58,532	$ 55,730	$ 54,415
Tier 1 (Core) Capital to average total assets Bank, actual ratio	0.102	0.1009	0.1008
Tier 1 (Core) Capital to average total assets Bank, to be well capitalized amount	$ 51,652	$ 49,724	$ 48,599
Tier 1 (Core) Capital to average total assets Bank, to be well capitalized ratio	0.09	0.09	0.09

Amount of total capital as defined by regulatory framework.

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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