Note 1 - Basis of Presentation and Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Number of Bank Branches	27
Number of Operating Segments	2
Cash, Uninsured Amount	$ 41,000	$ 27,000
Federal Home Loan Bank Stock	15,621,000	2,114,000
FHLB Impairment	0	0	$ 0
Marketing and Advertising Expense	1,310,000	1,349,000	897,000
Goodwill, Impairment Loss	$ 0	$ 0	$ 0
Building and Building Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	25 years
Furniture Fixtures and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	10 years
Furniture Fixtures and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years

The charge against FHLB stock.

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Represents the number bank branches.

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The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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The total expense recognized in the period for promotion, public relations, and brand or product advertising.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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