Note 12 - Fair Values - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale	$ 1,125,529	$ 1,102,230
US Treasury Securities [Member]
Debt Securities, Available-for-Sale	55,099	55,501
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale	687,508	639,773
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale	69,199	75,762
Municipal General Obligation Bonds [Member]
Debt Securities, Available-for-Sale	211,173	215,063
Municipal Revenue Bonds [Member]
Debt Securities, Available-for-Sale	63,628	65,004
Other Debt and Equity Securities [Member]
Debt Securities, Available-for-Sale	38,922	51,127
Fair Value, Recurring [Member]
Total assets	1,142,452	1,125,442
Total liabilities	17,126	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	1,142,452	1,125,442
Total liabilities	17,126	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	55,099	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	55,099	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	687,508	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	687,508	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	69,199	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	69,199	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	211,173	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	211,173	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	63,628	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	63,628	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	38,922	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	38,922	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	16,923	23,212
Interest rate swaps	17,126	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	16,923	23,212
Interest rate swaps	17,126	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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