Note 16 - Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2016

Notes Tables

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

	December 31, 2016				December 31, 2015
	Carrying				Carrying
	Amount		Fair Value		Amount		Fair Value
	(In thousands)
Financial Assets
Cash and due from banks	$	218,017	$	218,017	$	180,130	$	180,130
Short-term investments		967,067		967,067		536,880		536,880
Securities available-for-sale		1,314,345		1,314,345		1,586,352		1,586,352
Loans held for sale		7,500		7,500		6,676		6,676
Loans, net		11,077,315		11,006,344		10,016,227		9,938,810
Investment in Federal Home Loan Bank stock		17,250		17,250		17,250		17,250
Warrants		79		79		62		62

	Notional				Notional
	Amount		Fair Value		Amount		Fair Value
Foreign exchange contracts	$	82,439	$	1,302	$	100,602	$	3,339
Interest rate swaps		361,526		938		-		-

	Carrying				Carrying
	Amount		Fair Value		Amount		Fair Value
Financial Liabilities
Deposits	$	11,674,726	$	11,680,017	$	10,509,087	$	10,509,879
Securities sold under agreements to repurchase		350,000		351,989		400,000		413,417
Advances from Federal Home Loan Bank		350,000		350,062		275,000		274,488
Other borrowings		17,662		15,944		18,593		16,684
Long-term debt		119,136		63,169		119,136		58,420

	Notional				Notional
	Amount		Fair Value		Amount		Fair Value
Option contracts	$	12,117	$	121	$	9,396	$	28
Foreign exchange contracts		89,545		3,132		115,418		4,124
Interest rate swaps		119,136		3,744		459,416		6,496

	Notional					Notional
	Amount		Fair Value			Amount		Fair Value
Off-Balance Sheet Financial Instruments
Commitments to extend credit	$	2,062,241	$	(6,025	)	$	1,971,848	$	(5,570	)
Standby letters of credit		75,396		(668	)		49,081		(194	)
Other letters of credit		37,283		(16	)		38,131		(22	)
Bill of lading guarantees		75		(0	)		454		(1	)

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

	As of December 31, 2016
	Estimated
	Fair Value
	Measurements		Level 1		Level 2		Level 3
	(In thousands)
Financial Assets
Cash and due from banks	$	218,017	$	218,017	$	-	$	-
Short-term investments		967,067		967,067		-		-
Securities available-for-sale		1,314,345		513,376		800,969		-
Loans held-for-sale		7,500		-		-		7,500
Loans, net		11,006,344		-		-		11,006,344
Investment in Federal Home Loan Bank stock		17,250		-		17,250		-
Warrants		79		-		-		79
Financial Liabilities
Deposits		11,680,017		-		-		11,680,017
Securities sold under agreement to repurchase		351,989		-		351,989		-
Advances from Federal Home Loan Bank		350,062		-		350,062		-
Other borrowings		15,944		-		-		15,944
Long-term debt		63,169		-		63,169		-

	As of December 31, 2015
	Estimated
	Fair Value
	Measurements		Level 1		Level 2		Level 3
	(In thousands)
Financial Assets
Cash and due from banks	$	180,130	$	180,130	$	-	$	-
Short-term investments		536,880		536,880		-		-
Securities available-for-sale (1)		1,586,352		302,032		1,284,320		-
Loans held-for-sale		6,676		-		-		6,676
Loans, net		9,938,810		-		-		9,938,810
Investment in Federal Home Loan Bank stock		17,250		-		17,250		-
Warrants		62		-		-		62
Financial Liabilities
Deposits		10,509,879		-		-		10,509,879
Securities sold under agreement to repurchase		413,417		-		413,417		-
Advances from Federal Home Loan Bank		274,488		-		-		274,488
Other borrowings		16,684		-		-		16,684
Long-term debt		58,420		-		58,420		-