Note 6 - Investment Securities (Tables)

6 Months Ended

Jun. 30, 2016

Notes Tables

Schedule of Available-for-sale Securities Reconciliation [Table Text Block]

	June 30, 2016
			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses		Fair Value
	(In thousands)
Securities Available-for-Sale
U.S. treasury securities	$	239,811	$	228	$	-	$	240,039
U.S. government sponsored entities		125,000		142		-		125,142
Mortgage-backed securities		774,629		8,690		6		783,313
Collateralized mortgage obligations		56		-		24		32
Corporate debt securities		74,960		48		1,779		73,229
Mutual funds		6,000		-		47		5,953
Preferred stock of government sponsored entities		2,811		1,349		-		4,160
Other equity securities		3,902		6,134		-		10,036
Total	$	1,227,169	$	16,591	$	1,856	$	1,241,904

	December 31, 2015
			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses		Fair Value
	(In thousands)
Securities Available-for-Sale
U.S. treasury securities	$	284,678	$	5	$	395	$	284,288
U.S. government sponsored entities		150,000		-		1,840		148,160
Mortgage-backed securities		1,073,108		560		11,399		1,062,269
Collateralized mortgage obligations		63		-		27		36
Corporate debt securities		74,955		425		1,525		73,855
Mutual funds		6,000		-		167		5,833
Preferred stock of government sponsored entities		2,811		633		228		3,216
Other equity securities		4,108		4,929		342		8,695
Total	$	1,595,723	$	6,552	$	15,923	$	1,586,352

Investments Classified by Contractual Maturity Date [Table Text Block]

	Securities Available-For-Sale
	Amortized cost		Fair value
	(In thousands)
Due in one year or less	$	169,984	$	170,062
Due after one year through five years		254,283		253,727
Due after five years through ten years		20,324		19,639
Due after ten years (1)		782,578		798,476
Total	$	1,227,169	$	1,241,904

Schedule of Unrealized Loss on Investments [Table Text Block]

	June 30, 2016
	Temporarily impaired securities
	Less than 12 months				12 months or longer				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
	(Dollars in thousands)
Securities Available-for-Sale
Mortgage-backed securities	$	1,724	$	5	$	39	$	1	$	1,763	$	6
Collateralized mortgage obligations		-		-		32		24		32		24
Corporate debt securities		9,847		153		43,374		1,626		53,221		1,779
Mutual funds		-		-		5,953		47		5,953		47
Total	$	11,571	$	158	$	49,398	$	1,698	$	60,969	$	1,856

	December 31, 2015
	Temporarily impaired securities
	Less than 12 months				12 months or longer				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
	(Dollars in thousands)
Securities Available-for-Sale
U.S. treasury securities	$	224,289	$	395	$	-	$	-	$	224,289	$	395
U.S. government sponsored entities		148,160		1,840		-		-		148,160		1,840
Mortgage-backed securities		1,025,342		11,398		6		1		1,025,348		11,399
Collateralized mortgage obligations		-		-		36		27		36		27
Corporate debt securities		9,950		50		43,525		1,475		53,475		1,525
Mutual funds		-		-		5,833		167		5,833		167
Preferred stock of government sponsored entities		2,488		228		-		-		2,488		228
Other equity securities		158		342		-		-		158		342
Total	$	1,410,387	$	14,253	$	49,400	$	1,670	$	1,459,787	$	15,923