Investment Securities (Tables)

9 Months Ended

Sep. 30, 2018

Investments, Debt and Equity Securities [Abstract]

Schedule of amortized cost, gross unrealized gains, gross unrealized losses and the fair value of securities available-for-sale

The following tables present the amortized cost, gross unrealized gains, gross unrealized losses and the fair value for securities available-for-sale at September 30, 2018 and December 31, 2017:

	September 30, 2018
	Amortized cost		Gross unrealized gains	Gross unrealized (losses)		Fair value
			(In thousands)
U.S. government and agency obligations	$	54,813	—	(1,650	)	$	53,163
Mortgage-backed securities and collateralized mortgage obligations	902,572		321	(30,207	)	872,686
Municipal obligations	1,587		—	—		1,587
Corporate debt securities	54,492		13	(1,113	)	53,392
Trust preferred securities	5,000		—	(407	)	4,593
Equity securities	783		872	—		1,655
	$	1,019,247	1,206	(33,377	)	$	987,076

	December 31, 2017
	Amortized cost		Gross unrealized gains	Gross unrealized (losses)		Fair value
			(In thousands)
U.S. government and agency obligations	$	39,909	17	(282	)	$	39,644
Mortgage-backed securities and collateralized mortgage obligations	615,924		383	(9,695	)	606,612
Municipal obligations	1,957		—	—		1,957
Corporate debt securities	54,489		536	(511	)	54,514
Trust preferred securities	5,000		—	(344	)	4,656
Equity securities	2,328		859	—		3,187
	$	719,607	1,795	(10,832	)	$	710,570

Schedule of securities by contractual maturity

The table below presents the amortized cost and fair value of debt securities held-to-maturity at September 30, 2018 by contractual maturity. Expected maturities may differ from contractual maturities due to prepayment or early call privileges of the issuer.

	September 30, 2018
	Amortized cost		Fair value
	(In Thousands)
More than one year to five years	$	5,000	$	4,915
More than five years to ten years	8,404		7,997
More than ten years	10,000		9,945
	23,404		22,857
Mortgage-backed securities and collateralized mortgage obligations	240,780		228,560
	$	264,184	$	251,417

The table below presents the amortized cost and fair value of debt securities available-for-sale at September 30, 2018 by contractual maturity excluding equity securities. Expected maturities may differ from contractual maturities due to prepayment or early call privileges of the issuer.

	September 30, 2018
	Amortized cost		Fair value
	(In thousands)
One year or less	$	1,397	$	1,397
More than one year to five years	50,124		49,004
More than five years to ten years	59,371		57,890
More than ten years	5,000		4,444
	$	115,892	$	112,735
Mortgage-backed securities and collateralized mortgage obligations	902,572		872,686
	$	1,018,464	$	985,421

Schedule of available-for-sale securities reported in a continuous unrealized loss position

The following tables summarize the fair value and gross unrealized losses of those securities that reported an unrealized loss at September 30, 2018 and December 31, 2017 and if the unrealized loss position was continuous for the twelve months prior to September 30, 2018 and December 31, 2017:

	September 30, 2018
	Less than 12 months				12 months or longer			Total
	Fair Value		Gross unrealized (losses)		Fair value	Gross unrealized (losses)		Fair value	Gross unrealized (losses)
	(In thousands)
U.S. government and agency obligations	$	38,696	(1,169	)	14,467	(481	)	53,163	$	(1,650	)
Mortgage-backed securities and collateralized mortgage obligations	419,490		(8,722	)	383,623	(21,485	)	803,113	(30,207		)
Corporate debt securities	39,107		(384	)	9,271	(729	)	48,378	(1,113		)
Trust preferred securities	4,593		(407	)	—	—		4,593	(407		)
	$	501,886	(10,682	)	407,361	(22,695	)	909,247	$	(33,377	)

	December 31, 2017
	Less than 12 months				12 months or longer			Total
	Fair Value		Gross unrealized (losses)		Fair value	Gross unrealized (losses)		Fair value	Gross unrealized (losses)
	(In thousands)
U.S. government and agency obligations	$	29,654	(282	)	—	—		29,654	$	(282	)
Mortgage-backed securities and collateralized mortgage obligations	514,283		(8,037	)	48,788	(1,658	)	563,071	(9,695		)
Corporate debt securities	4,866		(135	)	4,624	(376	)	9,490	(511		)
Trust preferred securities	—		—		4,656	(344	)	4,656	(344		)
	$	548,803	(8,454	)	58,068	(2,378	)	606,871	$	(10,832	)

Schedule of amortized cost, gross unrealized gains, gross unrealized losses and the fair value of securities held-to-maturity

The following tables present the amortized cost, gross unrealized gains, gross unrealized losses and the fair value for securities held-to-maturity at September 30, 2018 and December 31, 2017:

	September 30, 2018
	Amortized cost		Gross unrealized gains	Gross unrealized (losses)		Fair value
	(In thousands)
U.S. government and agency obligations	$	23,404	—	(547	)	$	22,857
Mortgage-backed securities and collateralized mortgage obligations	240,780		344	(12,564	)	228,560
	$	264,184	344	(13,111	)	$	251,417

	December 31, 2017
	Amortized cost		Gross unrealized gains	Gross unrealized (losses)		Fair value
	(In thousands)
U.S. government and agency obligations	$	8,402	—	(58	)	$	8,344
Mortgage-backed securities and collateralized mortgage obligations	231,216		—	(3,435	)	227,781
	$	239,618	—	(3,493	)	$	236,125

Schedule of held-to-maturity securities reported in a continuous unrealized loss position

The following tables summarize the fair value and gross unrealized losses of those securities that reported an unrealized loss at September 30, 2018 and December 31, 2017 and if the unrealized loss position was continuous for the twelve months prior to September 30, 2018 and December 31, 2017:

	September 30, 2018
	Less than 12 months				12 months or longer			Total
	Fair Value		Gross unrealized (losses)		Fair value	Gross unrealized (losses)		Fair value	Gross unrealized (losses)
	(In thousands)
U.S. government and agency obligations	$	19,634	(362	)	3,223	(185	)	22,857	$	(547	)
Mortgage-backed securities and collateralized mortgage obligations	72,294		(2,835	)	145,768	(9,729	)	218,062	(12,564		)
	$	91,928	(3,197	)	148,991	(9,914	)	240,919	$	(13,111	)

	December 31, 2017
	Less than 12 months				12 months or longer			Total
	Fair Value		Gross unrealized (losses)		Fair value	Gross unrealized (losses)		Fair value	Gross unrealized (losses)
	(In thousands)
U.S. government and agency obligations	$	8,344	(58	)	—	—		8,344	$	(58	)
Mortgage-backed securities and collateralized mortgage obligations	196,049		(2,920	)	30,046	(515	)	226,095	(3,435		)
	$	204,393	(2,978	)	30,046	(515	)	234,439	$	(3,493	)