Note 12 - 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, 2024	Dec. 31, 2023
Securities available-for-sale	$ 1,508,356	$ 1,604,570
Equity securities	35,741	40,406
Derivative asset	32,807	54,268
Derivative liability	38,001	45,762
Fair Value, Recurring [Member]
Securities available-for-sale	1,508,356	1,604,570
Equity securities	34,202	40,406
Assets, fair value disclosure	1,575,900	1,699,623
Liabilities, fair value disclosure	38,694	45,937
Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Derivative asset	32,807	54,268
Derivative liability	38,001	45,762
Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Derivative asset	535	379
Derivative liability	693	175
Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	5,704	5,585
Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	2,514	1,821
Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	25,984	33,000
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	495,011	495,300
Equity securities	34,202	40,406
Assets, fair value disclosure	529,213	535,706
Liabilities, fair value disclosure	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Derivative asset	0	0
Derivative liability	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Derivative asset	0	0
Derivative liability	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	5,704	5,585
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	2,514	1,821
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	25,984	33,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	1,013,345	1,109,270
Equity securities	0	0
Assets, fair value disclosure	1,046,687	1,163,917
Liabilities, fair value disclosure	38,694	45,937
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Derivative asset	32,807	54,268
Derivative liability	38,001	45,762
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Derivative asset	535	379
Derivative liability	693	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]
Derivative asset	0	0
Derivative liability	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Derivative asset	0	0
Derivative liability	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	495,011	495,300
US Treasury Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	495,011	495,300
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	495,011	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	10,125	48,169
US Government Corporations and Agencies Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	10,125	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	10,125	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	734,536	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	734,536	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	26,434	28,044
Collateralized Mortgage Obligations [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	26,434	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	26,434	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	242,250	246,334
Corporate Debt Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	242,250	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	242,250	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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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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