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, 2025	Dec. 31, 2024
Securities available-for-sale	$ 1,643,450	$ 1,547,128
Equity securities	32,111	34,429
Interest rate swaps	29,162	39,958
Interest rate swaps	31,815	36,319
Fair Value, Recurring [Member]
Securities available-for-sale	1,643,450	1,547,128
Equity securities	30,572	32,890
Assets, fair value disclosure	1,703,505	1,620,466
Liabilities, fair value disclosure	32,000	37,104
Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	29,162	39,958
Interest rate swaps	31,815	36,319
Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Foreign exchange contracts	321	490
Foreign exchange contracts	185	785
Fair Value, Recurring [Member] \| Mutual Funds [Member]
Equity securities	5,686	5,532
Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	10,278	7,287
Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	14,608	20,071
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	776,833	621,462
Equity securities	30,572	32,890
Assets, fair value disclosure	807,405	654,352
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	5,686	5,532
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Preferred Stock of Government Sponsored Entities [Member]
Equity securities	10,278	7,287
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Other Equity Securities [Member]
Equity securities	14,608	20,071
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	866,617	925,666
Equity securities	0	0
Assets, fair value disclosure	896,100	966,114
Liabilities, fair value disclosure	32,000	37,104
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Interest rate swaps	29,162	39,958
Interest rate swaps	31,815	36,319
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Foreign exchange contracts	321	490
Foreign exchange contracts	185	785
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	776,833	621,462
US Treasury Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	776,833	621,462
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	776,833	621,462
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	6,860	9,149
US Government Corporations and Agencies Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	6,860	9,149
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	6,860	9,149
US Government Corporations and Agencies 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	25,005
US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	25,005
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	25,005
US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	0
Commercial Mortgage-Backed Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	645,575	684,016
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	645,575	684,016
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	23,302	24,556
Collateralized Mortgage Obligations [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	23,302	24,556
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	23,302	24,556
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	165,875	207,945
Corporate Debt Securities [Member] \| Fair Value, Recurring [Member]
Securities available-for-sale	165,875	207,945
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	165,875	207,945
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.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Fair value as of the balance sheet date of all derivative assets designated as foreign currency fair value hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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