Note 16 - Fair Value Measurements - Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Available-for-sale debt securities	$ 476,091	$ 522,566
Equity securities, at fair value	7,717	4,922
Interest rate swaps	1,946	371
US Treasury Securities [Member]
Available-for-sale debt securities	32,134	36,355
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale debt securities	220,782	244,372
Collateralized Mortgage-Backed Securities [Member]
Available-for-sale debt securities	20,663	25,506
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Available-for-sale debt securities	72,507	67,165
Corporate Debt Securities [Member]
Available-for-sale debt securities	30,672	32,063
Asset-Backed Securities [Member]
Available-for-sale debt securities	14,941	11,932
Negotiable Certificates of Deposit [Member]
Available-for-sale debt securities	656	736
Fair Value, Recurring [Member]
Available-for-sale debt securities	476,091	522,566
Equity securities, at fair value	7,717	4,922
Interest rate swaps	2,104	363
Total financial assets	485,912	527,851
Derivative liabilities	931	99
Total financial liabilities	931	99
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Equity securities, at fair value	7,717	4,922
Interest rate swaps	0	0
Total financial assets	7,717	4,922
Derivative liabilities	0	0
Total financial liabilities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	468,155	510,221
Equity securities, at fair value	0	0
Interest rate swaps	2,104	363
Total financial assets	470,259	510,584
Derivative liabilities	931	99
Total financial liabilities	931	99
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	7,936	12,345
Equity securities, at fair value	0	0
Interest rate swaps	0	0
Total financial assets	7,936	12,345
Derivative liabilities	0	0
Total financial liabilities	0	0
Fair Value, Recurring [Member] \| US Treasury Securities [Member]
Available-for-sale debt securities	32,134	36,355
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	32,134	36,355
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Available-for-sale debt securities	220,782	244,372
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	220,782	244,372
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Residential Mortgage [Member]
Available-for-sale debt securities	80,407	100,710
Fair Value, Recurring [Member] \| Residential Mortgage [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Residential Mortgage [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	80,407	100,710
Fair Value, Recurring [Member] \| Residential Mortgage [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Commercial Loan [Member]
Available-for-sale debt securities	3,329	3,727
Fair Value, Recurring [Member] \| Commercial Loan [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Commercial Loan [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	3,329	3,727
Fair Value, Recurring [Member] \| Commercial Loan [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member]
Available-for-sale debt securities	20,663	25,506
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	20,663	25,506
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Available-for-sale debt securities	72,507	67,165
Fair Value, Recurring [Member] \| Mortgage-Backed Securities, Issued by Private Enterprises [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Mortgage-Backed Securities, Issued by Private Enterprises [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	72,507	67,165
Fair Value, Recurring [Member] \| Mortgage-Backed Securities, Issued by Private Enterprises [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Available-for-sale debt securities	30,672	32,063
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	22,736	19,718
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	7,936	12,345
Fair Value, Recurring [Member] \| Asset-Backed Securities [Member]
Available-for-sale debt securities	14,941	11,932
Fair Value, Recurring [Member] \| Asset-Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Asset-Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	14,941	11,932
Fair Value, Recurring [Member] \| Asset-Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Negotiable Certificates of Deposit [Member]
Available-for-sale debt securities	656	736
Fair Value, Recurring [Member] \| Negotiable Certificates of Deposit [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale debt securities	0	0
Fair Value, Recurring [Member] \| Negotiable Certificates of Deposit [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale debt securities	656	736
Fair Value, Recurring [Member] \| Negotiable Certificates of Deposit [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale debt securities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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