Note 14 - Fair Value Measurements and Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Securities available-for-sale	$ 1,589,036	$ 1,658,223
Interest rate swaps	40,142	26,472
Interest rate swaps	36,243	28,917
Fair Value, Recurring [Member]
Securities available-for-sale	1,589,036	1,658,223
Equity securities	27,246	32,754
Assets, fair value disclosure	1,656,671	1,717,660
Liabilities, fair value disclosure	36,421	28,990
Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	40,142	26,472
Interest rate swaps	36,243	28,917
Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Foreign exchange contracts	247	211
Foreign exchange contracts	178	73
Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	8,304	8,691
Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	4,361	9,364
Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	14,581	14,699
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	924,647	828,193
Equity securities	27,246	32,754
Assets, fair value disclosure	951,893	860,947
Liabilities, fair value disclosure	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	0	0
Interest rate swaps	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Foreign exchange contracts	0	0
Foreign exchange contracts	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	8,304	8,691
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	4,361	9,364
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	14,581	14,699
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	664,389	830,030
Equity securities	0	0
Assets, fair value disclosure	704,778	856,713
Liabilities, fair value disclosure	36,421	28,990
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	40,142	26,472
Interest rate swaps	36,243	28,917
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Foreign exchange contracts	247	211
Foreign exchange contracts	178	73
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	0	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	0	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
Equity securities	0	0
Assets, fair value disclosure	0	0
Liabilities, fair value disclosure	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	0	0
Interest rate swaps	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Foreign exchange contracts	0	0
Foreign exchange contracts	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	0	0
US Treasury Securities [Member]
Securities available-for-sale	924,647	828,193
US Treasury Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	924,647	828,193
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	924,647	828,193
US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
US Government Corporations and Agencies Securities [Member]
Securities available-for-sale	578	5,822
US Government Corporations and Agencies Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	578	5,822
US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	578	5,822
US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
Commercial Mortgage-Backed Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	634,617	629,437
Commercial Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
Commercial Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	634,617	629,437
Commercial Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
US Government-sponsored Enterprises Debt Securities [Member]
Securities available-for-sale		25,011
US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale		25,011
US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale		0
US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale		25,011
US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale		0
Collateralized Mortgage Obligations [Member]
Securities available-for-sale	4,209	22,748
Collateralized Mortgage Obligations [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	4,209	22,748
Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	4,209	22,748
Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
Corporate Debt Securities [Member]
Securities available-for-sale	24,985	147,012
Corporate Debt Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	24,985	147,012
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	24,985	147,012
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	$ 0	$ 0

Fair value portion of asset recognized for present right to economic benefit.

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Amount excluding accrued interest, 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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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Fair value as of the balance sheet date of all derivative assets designated as foreign currency fair value hedging instruments.

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Fair value as of the balance sheet date of all derivative liabilities designated as foreign currency fair value hedging instruments.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Fair value of financial and nonfinancial obligations.

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