Debt Securities Available for Sale (Tables)

9 Months Ended

Sep. 30, 2020

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

Debt securities available for sale at September 30, 2020 and December 31, 2019 are summarized as follows:

	September 30, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
			(In thousands)
U.S. government and agency obligations	$	29,421	$	1,247	$	—	$	30,668
Mortgage-backed securities and collateralized mortgage obligations	1,095,120		39,429		(443)		1,134,106
Municipal obligations	1,870		15		—		1,885
Corporate debt securities	72,590		2,096		(505)		74,181
Trust preferred securities	5,000		—		(540)		4,460
	$	1,204,001	$	42,787	$	(1,488)	$	1,245,300

	December 31, 2019
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
			(In thousands)
U.S. government and agency obligations	$	42,081	$	321	$	(16)	$	42,386
Mortgage-backed securities and collateralized mortgage obligations	968,165		12,981		(1,265)		979,881
Municipal obligations	2,284		1		(1)		2,284
Corporate debt securities	68,613		945		(378)		69,180
Trust preferred securities	5,000		—		(395)		4,605
	$	1,086,143	$	14,248	$	(2,055)	$	1,098,336

Schedule of securities by contractual maturity

The amortized cost and fair value of debt securities available for sale at September 30, 2020, by contractual final maturity, is shown below. Expected maturities may differ from contractual maturities due to prepayment or early call options exercised by the issuer.

	September 30, 2020
	Amortized Cost		Fair Value
	(In thousands)
One year or less	$	16,399	$	16,416
More than one year to five years	42,422		44,295
More than five years to ten years	49,590		50,000
More than ten years	470		483
	$	108,881	$	111,194
Mortgage-backed securities and collateralized mortgage obligations	1,095,120		1,134,106
	$	1,204,001	$	1,245,300

Debt securities, available-for-sale, unrealized loss position, fair value

The following tables summarize the fair value and gross unrealized losses of those securities that reported an unrealized loss at September 30, 2020 and December 31, 2019 and if the unrealized loss position was continuous for the twelve months prior to those respective dates:

	September 30, 2020
	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)
Mortgage-backed securities and collateralized mortgage obligations	$	138,268	$	(367)	$	36,897	$	(76)	$	175,165	$	(443)
Corporate debt securities	993		(7)		4,503		(498)		5,496		(505)
Trust preferred securities	—		—		4,459		(540)		4,459		(540)
	$	139,261	$	(374)	$	45,859	$	(1,114)	$	185,120	$	(1,488)

6.    Debt Securities Available for Sale (continued)

	December 31, 2019
	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	$	5,106	$	(13)	$	4,988	$	(3)	$	10,094	$	(16)
Mortgage-backed securities and collateralized mortgage obligations	178,665		(946)		58,208		(319)		236,873		(1,265)
Municipal obligations	696		(1)		—		—		696		(1)
Corporate debt securities	2,588		(5)		4,627		(373)		7,215		(378)
Trust preferred securities	—		—		4,605		(395)		4,605		(395)
	$	187,055	$	(965)	$	72,428	$	(1,090)	$	259,483	$	(2,055)