Note 11 - Fair Values - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale, Total	$ 582,999,000	$ 592,743,000
Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Total	0	0
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale, Total	385,456,000	390,371,000
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Total	32,657,000	41,803,000
Municipal General Obligation Bonds [Member]
Debt Securities, Available-for-Sale, Total	142,021,000	137,594,000
Municipal Revenue Bonds [Member]
Debt Securities, Available-for-Sale, Total	22,365,000	22,475,000
Other Debt and Equity Securities [Member]
Debt Securities, Available-for-Sale, Total	500,000	500,000
Fair Value, Recurring [Member]
Total assets	611,444,000	597,352,000
Total liabilities	28,544,000	4,857,000
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Total assets	610,821,000	596,675,000
Total liabilities	28,544,000	4,857,000
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total assets	623,000	677,000
Total liabilities	0	0
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale, Total	385,456,000	390,371,000
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Total	385,456,000	390,371,000
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Total	32,657,000	41,803,000
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Total	32,657,000	41,803,000
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member]
Debt Securities, Available-for-Sale, Total	142,021,000	137,594,000
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Total	141,398,000	136,917,000
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Total	623,000	677,000
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member]
Debt Securities, Available-for-Sale, Total	22,365,000	22,475,000
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Total	22,365,000	22,475,000
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| Other Debt and Equity Securities [Member]
Debt Securities, Available-for-Sale, Total	500,000	500,000
Fair Value, Recurring [Member] \| Other Debt and Equity Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| Other Debt and Equity Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Total	500,000	500,000
Fair Value, Recurring [Member] \| Other Debt and Equity Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Total	0	0
Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	28,445,000	4,609,000
Interest rate swaps	28,544,000	4,857,000
Fair Value, Recurring [Member] \| Interest Rate Swap [Member] \| Fair Value, Inputs, Level 1 [Member]
Interest rate swaps	0	0
Interest rate swaps	0	0
Fair Value, Recurring [Member] \| Interest Rate Swap [Member] \| Fair Value, Inputs, Level 2 [Member]
Interest rate swaps	28,445,000	4,609,000
Interest rate swaps	28,544,000	4,857,000
Fair Value, Recurring [Member] \| Interest Rate Swap [Member] \| Fair Value, Inputs, Level 3 [Member]
Interest rate swaps	0	0
Interest rate swaps	$ 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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