Note 11 - Fair Values (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale, Total	$ 434,257,000	$ 387,347,000
Mortgages Held-for-sale, Fair Value Disclosure	$ 41,300,000	24,000,000.0
Real Estate Dependent Loans and Foreclosed Assets Estimated Selling Costs [Member]
Fair Value Inputs, Discount Factor	10.00%
Real Estate Dependent Loans and Foreclosed Assets [Member] | Commercial Real Estate [Member] | Minimum [Member]
Fair Value Inputs, Discount Factor	15.00%
Real Estate Dependent Loans and Foreclosed Assets [Member] | Commercial Real Estate [Member] | Maximum [Member]
Fair Value Inputs, Discount Factor	25.00%
Real Estate Dependent Loans and Foreclosed Assets [Member] | Residential Real Estate [Member] | Minimum [Member]
Fair Value Inputs, Discount Factor	25.00%
Real Estate Dependent Loans and Foreclosed Assets [Member] | Residential Real Estate [Member] | Maximum [Member]
Fair Value Inputs, Discount Factor	50.00%
Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-sale, Total	$ 0	0
Available-for-sale Securities [Member]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Ending Balance	$ 0	$ 0