Note 6 - Fair Value Measurements - Assets and Liabilities at Fair Value on Recurring Basis (Details) $ in Thousands		Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Securities available for sale		$ 622,271	$ 618,601
Interest Rate Loan Contract [Member] | Valuation, Market Approach [Member] | Measurement Input, Pull-through Rate [Member]
Derivative Asset, Measurement Input	[1]		1
Interest Rate Loan Contract [Member] | Valuation, Market Approach [Member] | Measurement Input, Current Reference Price [Member]
Derivative Asset, Measurement Input	[2]		1.0264
Interest Rate Loan Contract [Member] | Fair Value, Recurring [Member]
Derivative Asset			$ 3
Forward Sale Commitment [Member] | Valuation, Market Approach [Member] | Measurement Input, Pull-through Rate [Member]
Derivative Liability, Measurement Input	[1]	1	1
Forward Sale Commitment [Member] | Valuation, Market Approach [Member] | Measurement Input, Current Reference Price [Member] | Maximum [Member]
Derivative Liability, Measurement Input	[3]	1.0263	1.0264
Forward Sale Commitment [Member] | Valuation, Market Approach [Member] | Measurement Input, Current Reference Price [Member] | Minimum [Member]
Derivative Liability, Measurement Input	[3]	1.0199	1.016
Forward Sale Commitment [Member] | Valuation, Market Approach [Member] | Measurement Input, Current Reference Price [Member] | Weighted Average [Member]
Derivative Liability, Measurement Input	[3]	1.0214	1.0198
Forward Sale Commitment [Member] | Fair Value, Recurring [Member]
Derivative Liability		$ (3)	$ (4)
Fair Value, Inputs, Level 1 [Member]
Securities available for sale		0	0
Fair Value, Inputs, Level 2 [Member]
Securities available for sale		622,271	618,601
Fair Value, Inputs, Level 3 [Member]
Securities available for sale		0	0
Fair Value, Inputs, Level 3 [Member] | Interest Rate Loan Contract [Member] | Fair Value, Recurring [Member]
Derivative Asset			3
Fair Value, Inputs, Level 3 [Member] | Forward Sale Commitment [Member] | Fair Value, Recurring [Member]
Derivative Liability		(3)	(4)
US Government Agencies Debt Securities [Member]
Securities available for sale		320,432	311,844
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Securities available for sale		0	0
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available for sale		320,432	311,844
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available for sale		0	0
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale		152,728	149,893
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Securities available for sale		0	0
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available for sale		152,728	149,893
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available for sale		0	0
Collateralized Mortgage-Backed Securities [Member]
Securities available for sale		142,245	150,151
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Securities available for sale		0	0
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available for sale		142,245	150,151
Collateralized Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available for sale		0	0
Corporate Debt Securities [Member]
Securities available for sale		5,876	5,750
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Securities available for sale		0	0
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available for sale		5,876	5,750
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available for sale		0	0
US Treasury Securities [Member]
Securities available for sale		990	963
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Securities available for sale		0	0
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available for sale		990	963
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available for sale		$ 0	$ 0

[1] All contracts are valued using the same pull-through rate

[2] Comprised of only one loan.

[3] Current reference prices were weighted by the relative amount of the loan