Note 7 - Investment Securities (Tables)

3 Months Ended

Mar. 31, 2018

Notes Tables

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

	March 31, 2018
			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses		Fair Value
	(In thousands)
Debt Securities Available-for-Sale
U.S. treasury securities	$	124,842	$	-	$	247	$	124,595
U.S. government agency entities		8,794		-		99		8,695
U.S. government sponsored entities		400,000		-		14,080		385,920
State and municipal securities		924				20		904
Mortgage-backed securities		655,327		226		17,194		638,359
Collateralized mortgage obligations		1,398		-		27		1,371
Corporate debt securities		80,006		1,280		25		81,261
Total	$	1,271,291	$	1,506	$	31,692	$	1,241,105

	December 31, 2017
			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses		Fair Value
	(In thousands)
Securities Available-for-Sale
U.S. treasury securities	$	249,877	$	-	$	357	$	249,520
U.S. government agency entities		9,047		11		70		8,988
U.S. government sponsored entities		400,000		-		9,664		390,336
State and municipal securities		1,944		-		30		1,914
Mortgage-backed securities		577,987		241		6,259		571,969
Collateralized mortgage obligations		1,533		-		17		1,516
Corporate debt securities		80,007		1,291		17		81,281
Mutual funds		6,500		-		270		6,230
Preferred stock of government sponsored entities		5,842		4,260		-		10,102
Other equity securities		3,608		8,162		-		11,770
Total	$	1,336,345	$	13,965	$	16,684	$	1,333,626

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	$	140,165	$	139,922
Due after one year through five years		466,090		453,280
Due after five years through ten years		5,783		5,624
Due after ten years		659,253		642,279
Total	$	1,271,291	$	1,241,105

Schedule of Unrealized Loss on Investments [Table Text Block]

	March 31, 2018
	Temporarily impaired securities
	Less than 12 months				12 months or longer				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
	(In thousands)
Debt Securities Available-for-Sale
U.S. treasury securities	$	74,829	$	19	$	49,766	$	228	$	124,595	$	247
U.S. government agency entities		8,695		99		-		-		8,695		99
U.S. government sponsored entities		-		-		385,920		14,080		385,920		14,080
State and municipal securities		903		20		-		-		903		20
Mortgage-backed securities		437,818		11,042		167,958		6,152		605,776		17,194
Collateralized mortgage obligations		1,371		27		-		-		1,371		27
Corporate debt securities		5,003		25		-		-		5,003		25
Total debt securities	$	528,619	$	11,232	$	603,644	$	20,460	$	1,132,263	$	31,692
Equity Securities
Preferred stock of government sponsored entities		6,691		3,411		-		-		6,691		3,411
Mutual funds		-		-		6,129		371		6,129		371
Other equity securities		11,334		436		-		-		11,334		436
Total equity securities	$	18,025	$	3,847	$	6,129	$	371	$	24,154	$	4,218

	December 31, 2017
	Temporarily impaired securities
	Less than 12 months				12 months or longer				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
	(In thousands)
Securities Available-for-Sale
U.S. treasury securities	$	199,823	$	62	$	49,697	$	295	$	249,520	$	357
U.S. government agency entities		5,711		70		-		-		5,711		70
U.S. government sponsored entities		-		-		390,336		9,664		390,336		9,664
State and municipal securities		1,914		30		-		-		1,914		30
Mortgage-backed securities		342,436		3,147		178,617		3,112		521,053		6,259
Collateralized mortgage obligations		1,516		17		-		-		1,516		17
Corporate debt securities		5,015		17		-		-		5,015		17
Mutual funds		-		-		6,230		270		6,230		270
Total	$	556,415	$	3,343	$	624,880	$	13,341	$	1,181,295	$	16,684