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Note 10 - Borrowed Funds (Details Textual) - USD ($)		48 Months Ended
Note 10 - Borrowed Funds (Details Textual) - USD ($)	Sep. 30, 2020	Sep. 30, 2025	Dec. 31, 2025	Sep. 25, 2025
Long-Term Debt, Maturity, Year Five			$ 9,900,000
Unsecured Line of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity			23,500,000
Federal Home Loan Bank Advances [Member]
Line of Credit Facility, Maximum Borrowing Capacity			84,200,000
Federal Reserve Bank Advances [Member]
Line of Credit Facility, Maximum Borrowing Capacity			$ 29,300,000
Subordinated Debt [Member]
Debt Instrument, Face Amount				$ 12,500,000
Debt Instrument, Interest Rate, Stated Percentage				7.875%
Loan to Fund Merger Consideration [Member]
Debt Instrument, Face Amount	$ 17,000,000
Payments of Debt Issuance Costs	28,100
Proceeds from Issuance of Long-Term Debt	$ 16,900,000
Debt Instrument, Interest Rate, Stated Percentage	4.10%
Debt Instrument, Periodic Payment		$ 646,500