Note 15 - Fair Value Measurements - Assets and Liabilities at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Securities available for sale	$ 656,852	$ 686,080
Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Inputs, Level 2 [Member]
Securities available for sale	656,852	686,080
Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
US Government Agencies Debt Securities [Member]
Securities available for sale	336,575	278,019
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	336,575	278,019
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	152,200	198,672
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	152,200	198,672
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	161,477	206,174
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	161,477	206,174
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	5,664	3,215
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	5,664	3,215
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	$ 0
US Treasury Securities [Member]
Securities available for sale	936
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Securities available for sale
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available for sale	936
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available for sale