Note 17 - Fair Value Measurements and Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2023

Notes Tables

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

As of December 31, 2023	Fair Value Measurements Using						Total at
	Level 1		Level 2		Level 3		Fair Value
Assets	(In thousands)
Securities available-for-sale
U.S. Treasury securities	$	495,300	$	—	$	—	$	495,300
U.S. government agency entities		—		48,169		—		48,169
U.S. government sponsored entities		—		—		—		—
Mortgage-backed securities		—		786,723		—		786,723
Collateralized mortgage obligations		—		28,044		—		28,044
Corporate debt securities		—		246,334		—		246,334
Total securities available-for-sale		495,300		1,109,270		—		1,604,570
Equity securities
Mutual funds		5,585		—		—		5,585
Preferred stock of government sponsored entities		1,821		—		—		1,821
Other equity securities		33,000		—		—		33,000
Total equity securities		40,406		—		—		40,406
Warrants		—		—		—		—
Interest rate swaps		—		54,268		—		54,268
Foreign exchange contracts				379		—		379
Total assets	$	535,706	$	1,163,917	$	—	$	1,699,623
Liabilities
Interest rate swaps	$	—	$	45,762	$	—	$	45,762
Foreign exchange contracts		—		175		—		175
Total liabilities	$	—	$	45,937	$	—	$	45,937

As of December 31, 2022	Fair Value Measurements Using						Total at
	Level 1		Level 2		Level 3		Fair Value
Assets	(In thousands)
Securities available-for-sale
U.S. Treasury securities	$	240,500	$	—	$	—	$	240,500
U.S. government agency entities		—		63,610		—		63,610
U.S. government sponsored entities		—		30,000		—		30,000
Mortgage-backed securities		—		867,094		—		867,094
Collateralized mortgage obligations		—		31,061		—		31,061
Corporate debt securities		—		241,083		—		241,083
Total securities available-for-sale		240,500		1,232,848		—		1,473,348
Equity securities
Mutual funds		5,509		—		—		5,509
Preferred stock of government sponsored entities		1,289		—		—		1,289
Other equity securities		15,360		—		—		15,360
Total equity securities		22,158		—		—		22,158
Warrants		—		—		50		50
Interest rate swaps		—		44,443		—		44,443
Foreign exchange contracts		—		448		—		448
Total assets	$	262,658	$	1,277,739	$	50	$	1,540,447
Liabilities
Interest rate swaps	$	—	$	51,864	$	—	$	51,864
Foreign exchange contracts		—		942		—		942
Total liabilities	$	—	$	52,806	$	—	$	52,806

Fair Value Measurements, Nonrecurring [Table Text Block]

	As of December 31, 2023								Total Losses
	Fair Value Measurements Using						Total at		For the Twelve Months Ended
	Level 1		Level 2		Level 3		Fair Value		December 31, 2023		December 31, 2022
Assets	(In thousands)
Non-accrual loans by type:
Commercial loans	$	—	$	—	$	191	$	191	$	—	$	1,786
Commercial real estate loans		—		—		6,882		6,882		4,069		2,091
Total non-accrual loans		—		—		7,073		7,073		4,069		3,877
Other real estate owned (1)		—		—		20,446		20,446		—		—
Investments in venture capital		—		—		237		237		227		268
Total assets	$	—	$	—	$	27,756	$	27,756	$	4,296	$	4,145

	As of December 31, 2022								Total Losses
	Fair Value Measurements Using						Total at		For the Twelve Months Ended
	Level 1		Level 2		Level 3		Fair Value		December 31, 2022		December 31, 2021
Assets	(In thousands)
Non-accrual loans by type:
Commercial loans	$	—	$	—	$	12,950	$	12,950	$	1,786	$	1,012
Commercial real estate loans		—		—		32,205		32,205		2,091		—
Residential mortgage and equity lines		—		—		8,978		8,978		—		—
Installment and other loans		—		—		8		8		—		—
Total non-accrual loans		—		—		54,141		54,141		3,877		1,012
Other real estate owned (1)		—		—		4,328		4,328		—		17
Investments in venture capital		—		—		689		689		268		143
Total assets	$	—	$	—	$	59,158	$	59,158	$	4,145	$	1,172

Fair Value, by Balance Sheet Grouping [Table Text Block]

	December 31, 2023				December 31, 2022
	Carrying				Carrying
	Amount		Fair Value		Amount		Fair Value
	(In thousands)
Financial Assets
Cash and due from banks	$	173,988	$	173,988	$	195,440	$	195,440
Short-term investments		654,813		654,813		966,962		966,962
Securities available-for-sale		1,604,570		1,604,570		1,473,348		1,473,348
Loans, net		19,382,858		19,605,152		18,100,898		17,944,588
Equity securities		40,406		40,406		22,158		22,158
Investment in Federal Home Loan Bank stock		17,746		17,746		17,250		17,250
Warrants		—		—		50		50

	Notional				Notional
	Amount		Fair Value		Amount		Fair Value
Foreign exchange contracts	$	124,452	$	379	$	72,996	$	448
Interest rate swaps		1,406,879		54,268		817,615		44,443

Financial Liabilities	Carrying				Carrying
	Amount		Fair Value		Amount		Fair Value
Deposits	$	19,325,447	$	19,347,070	$	18,505,279	$	18,572,387
Advances from Federal Home Loan Bank		540,000		536,996		485,000		482,737
Other borrowings		15,787		13,978		22,600		18,385
Long-term debt		119,136		72,304		119,136		68,231

	Notional				Notional
	Amount		Fair Value		Amount		Fair Value
Foreign exchange contracts		101,378		175		170,213		942
Interest rate swaps		1,078,880		45,762		595,426		51,864

	Notional					Notional
	Amount		Fair Value			Amount		Fair Value
Off-Balance Sheet Financial Instruments
Commitments to extend credit	$	3,808,620	$	(14,344	)	$	3,630,304	$	(14,797	)
Standby letters of credit		368,618		(2,821	)		315,821		(2,738	)
Other letters of credit		11,308		(10	)		29,416		(33	)

Schedule Of Fair Value Of Financial Instruments [Table Text Block]

	As of December 31, 2023
	Estimated
	Fair Value
	Measurements		Level 1		Level 2		Level 3
	(In thousands)
Financial Assets
Cash and due from banks	$	173,988	$	173,988	$	—	$	—
Short-term investments		654,813		654,813		—		—
Loans, net		19,605,152		—		—		19,605,152
Equity securities		40,406		40,406		—		—
Investment in Federal Home Loan Bank stock		17,746		—		17,746		—
Warrants		—		—		—		—
Financial Liabilities
Deposits		19,347,070		—		—		19,347,070
Advances from Federal Home Loan Bank		536,996		—		536,996		—
Other borrowings		13,978		—		—		13,978
Long-term debt		72,304		—		72,304		—

	As of December 31, 2022
	Estimated
	Fair Value
	Measurements		Level 1		Level 2		Level 3
	(In thousands)
Financial Assets
Cash and due from banks	$	195,440	$	195,440	$	—	$	—
Short-term investments		966,962		966,962		—		—
Loans, net		17,944,588		—		—		17,944,588
Equity securities		22,158		22,158		—		—
Investment in Federal Home Loan Bank stock		17,250		—		17,250		—
Warrants		50		—		—		50
Financial Liabilities
Deposits		18,572,387		—		—		18,572,387
Advances from Federal Home Loan Bank		482,737		—		482,737		—
Other borrowings		18,385		—		—		18,385
Long-term debt		68,231		—		68,231		—