Note 16 - Fair Value Measurements and Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Securities available-for-sale	$ 1,547,128	$ 1,604,570
Equity securities	34,429	40,406
Interest rate swaps	39,958	54,268
Interest rate swaps	36,319	45,762
Fair Value, Recurring [Member]
Securities available-for-sale	1,547,128	1,604,570
Equity securities	32,890	40,406
Assets, fair value disclosure	1,620,466	1,699,623
Liabilities, fair value disclosure	37,104	45,937
Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	39,958	54,268
Interest rate swaps	36,319	45,762
Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Foreign exchange contracts	490	379
Foreign exchange contracts	785	175
Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	5,532	5,585
Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	7,287	1,821
Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	20,071	33,000
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	621,462	495,300
Equity securities	32,890	40,406
Assets, fair value disclosure	654,352	535,706
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
Foreign exchange contracts	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	5,532	5,585
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	7,287	1,821
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	20,071	33,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	925,666	1,109,270
Equity securities	0	0
Assets, fair value disclosure	966,114	1,163,917
Liabilities, fair value disclosure	37,104	45,937
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	39,958	54,268
Interest rate swaps	36,319	45,762
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Foreign exchange contracts	490	379
Foreign exchange contracts	785	175
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	621,462	495,300
US Treasury Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	621,462	495,300
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	621,462	495,300
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	9,149	48,169
US Government Corporations and Agencies Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	9,149	48,169
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	9,149	48,169
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	684,016	786,723
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	684,016	786,723
Commercial Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0	0
Collateralized Mortgage Obligations [Member]
Securities available-for-sale	24,556	28,044
Collateralized Mortgage Obligations [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	24,556	28,044
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	24,556	28,044
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	207,945	246,334
Corporate Debt Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	207,945	246,334
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	207,945	246,334
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 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 of financial and nonfinancial obligations.

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