Note 12 - Fair Values - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-Sale	$ 855,138	$ 730,352
Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale	0	0
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale	606,782	495,581
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale	23,673	25,368
Municipal General Obligation Bonds [Member]
Debt Securities, Available-for-Sale	192,575	180,170
Municipal Revenue Bonds [Member]
Debt Securities, Available-for-Sale	31,608	28,733
Other Debt and Equity Securities [Member]
Debt Securities, Available-for-Sale	500	500
Fair Value, Recurring [Member]
Total assets	880,241	757,145
Total liabilities	25,515	27,050
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	879,863	756,752
Total liabilities	25,515	27,050
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total assets	378	393
Total liabilities	0	0
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale	606,782	495,581
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	606,782	495,581
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	23,673	25,368
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	23,673	25,368
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	192,575	180,170
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	192,197	179,777
Fair Value, Recurring [Member] \| Municipal General Obligation Bonds [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale	378	393
Fair Value, Recurring [Member] \| Municipal Revenue Bonds [Member]
Debt Securities, Available-for-Sale	31,608	28,733
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	31,608	28,733
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	500	500
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	500	500
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	25,103	26,793
Interest rate swaps	25,515	27,050
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	25,103	26,793
Interest rate swaps	25,515	27,050
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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