Note 12 - Fair Values - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale	$ 1,098,016	$ 1,102,230
US Treasury Securities [Member]
Debt Securities, Available-for-Sale	50,414	55,501
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale	682,002	639,773
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale	68,712	75,762
Municipal General Obligation Bonds [Member]
Debt Securities, Available-for-Sale	199,010	215,063
Municipal Revenue Bonds [Member]
Debt Securities, Available-for-Sale	61,647	65,004
Other Debt and Equity Securities [Member]
Debt Securities, Available-for-Sale	36,231	51,127
Fair Value, Recurring [Member]
Total assets	1,126,494	1,125,442
Total liabilities	28,559	23,532
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	1,126,494	1,125,442
Total liabilities	28,559	23,532
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring [Member] \| US Treasury Securities [Member]
Debt Securities, Available-for-Sale	50,414	55,501
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale	50,414	55,501
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale	682,002	639,773
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale	682,002	639,773
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale	68,712	75,762
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale	68,712	75,762
Fair Value, Recurring [Member] \| Collateralized Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member]
Debt Securities, Available-for-Sale	199,010	215,063
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale	199,010	215,063
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member]
Debt Securities, Available-for-Sale	61,647	65,004
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale	61,647	65,004
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Other Debt and Equity Securities [Member]
Debt Securities, Available-for-Sale	36,231	51,127
Fair Value, Recurring [Member] \| Other Debt and Equity Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Other Debt and Equity Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale	36,231	51,127
Fair Value, Recurring [Member] \| Other Debt and Equity Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale	0	0
Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	28,478	23,212
Interest rate swaps	28,559	23,532
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	28,478	23,212
Interest rate swaps	28,559	23,532
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 asset recognized for present right to economic benefit.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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