Note 11 - Fair Values (Details Textual) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale	$ 592,305,000	$ 592,305,000	$ 602,936,000
Loan, Mortgage, Held-for-Sale, Fair Value Disclosure	$ 10,200,000	10,200,000	3,600,000
Real Estate Dependent Loans and Foreclosed Assets Estimated Selling Costs [Member]
Fair Value Inputs, Discount Factor	10.00%
Maximum [Member] | Real Estate Dependent Loans and Foreclosed Assets [Member] | Commercial Real Estate [Member]
Fair Value Inputs, Discount Factor	35.00%
Maximum [Member] | Real Estate Dependent Loans and Foreclosed Assets [Member] | Residential Real Estate [Member]
Fair Value Inputs, Discount Factor	50.00%
Minimum [Member] | Real Estate Dependent Loans and Foreclosed Assets [Member] | Commercial Real Estate [Member]
Fair Value Inputs, Discount Factor	25.00%
Minimum [Member] | Real Estate Dependent Loans and Foreclosed Assets [Member] | Residential Real Estate [Member]
Fair Value Inputs, Discount Factor	25.00%
Municipal General Obligation Bonds [Member]
Debt Securities, Available-for-Sale	$ 153,425,000	153,425,000	154,433,000
Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale	0	0	0
Fair Value, Inputs, Level 3 [Member] | Municipal General Obligation Bonds [Member] | Maximum [Member]
Debt Securities, Available-for-Sale, Decrease Due to Scheduled Maturities		100,000	100,000
Available-for-Sale Securities [Member]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Ending Balance	$ 0	$ 0	$ 0