Note 12 - Fair Value Measurements - Financial Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Securities available for sale	$ 643,949	$ 466,091
US Treasury Securities [Member]
Securities available for sale	110,041	34,998
US Government-sponsored Enterprises Debt Securities [Member]
Securities available for sale	90,496	106,023
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale	63,867	59,099
Corporate Debt Securities [Member]
Securities available for sale	19,138	13,189
Fair Value, Recurring [Member]
Securities available for sale	643,949	466,091
Loans held for sale	9,518	15,591
Fair Value, Recurring [Member] \| Cash Flow Hedging [Member]
Derivative - cash flow hedges	3,265	4,868
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Loans held for sale	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Cash Flow Hedging [Member]
Derivative - cash flow hedges	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	643,949	466,091
Loans held for sale	9,518	15,591
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Cash Flow Hedging [Member]
Derivative - cash flow hedges	3,265	4,868
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Loans held for sale	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Cash Flow Hedging [Member]
Derivative - cash flow hedges	0	0
Fair Value, Recurring [Member] \| US Treasury Securities [Member]
Securities available for sale	110,041	34,998
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	110,041	34,998
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| US Government-sponsored Enterprises Debt Securities [Member]
Securities available for sale	90,496	106,023
Fair Value, Recurring [Member] \| US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	90,496	106,023
Fair Value, Recurring [Member] \| US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member]
Securities available for sale	360,408	252,782
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	360,408	252,782
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Securities available for sale	63,866	59,099
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	63,866	59,099
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Securities available for sale	19,138	13,189
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	19,138	13,189
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	$ 0	$ 0