Debt Securities Available for Sale (Tables)

3 Months Ended

Mar. 31, 2022

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 March 31, 2022 and December 31, 2021 are summarized as follows:

	March 31, 2022
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Allowance for Credit Losses		Fair Value
	(In thousands)
U.S. government and agency obligations	$	43,185	$	80	$	(1,178)	$	—	$	42,087
Mortgage-backed securities and collateralized mortgage obligations	1,488,048		2,075		(75,981)		—		1,414,142
Municipal obligations	4,157		—		(5)		(11)		4,141
Corporate debt securities	122,720		1,085		(3,545)		(1,133)		119,127
	$	1,658,110	$	3,240	$	(80,709)	$	(1,144)	$	1,579,497

	December 31, 2021
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)		Fair Value
			(In thousands)
U.S. government and agency obligations	$	34,711	$	404	$	(236)	$	34,879
Mortgage-backed securities and collateralized mortgage obligations	1,553,491		14,141		(13,273)		1,554,359
Municipal obligations	4,159		20		—		4,179
Corporate debt securities	109,018		2,378		(966)		110,430
	$	1,701,379	$	16,943	$	(14,475)	$	1,703,847

Schedule of securities by contractual maturity

The amortized cost and fair value of debt securities available for sale at March 31, 2022, 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.

	March 31, 2022
	Amortized Cost		Fair Value
	(In thousands)
One year or less	$	16,907	$	16,947
More than one year to five years	73,239		72,878
More than five years to ten years	79,916		75,530
	$	170,062	$	165,355
Mortgage-backed securities and collateralized mortgage obligations	1,488,048		1,414,142
	$	1,658,110	$	1,579,497

The amortized cost and fair value of debt securities held to maturity at March 31, 2022, 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.

	March 31, 2022
	Amortized Cost		Fair Value
	(In thousands)
More than one year to five years	$	14,875	$	14,113
More than five years to ten years	19,996		18,381
More than ten years	10,000		9,019
	44,871		41,513
Mortgage-backed securities and collateralized mortgage obligations	374,162		357,511
	$	419,033	$	399,024

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 March 31, 2022 and December 31, 2021 and if the unrealized loss position was continuous for the twelve months prior to those respective dates:

	March 31, 2022
	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	$	22,400	$	(806)	$	4,613	$	(372)	$	27,013	$	(1,178)
Mortgage-backed securities and collateralized mortgage obligations	1,010,976		(52,254)		265,384		(23,727)		1,276,360		(75,981)
Municipal obligations	452		(5)		—		—		452		(5)
Corporate debt securities	63,295		(3,222)		4,632		(323)		67,927		(3,545)
	$	1,097,123	$	(56,287)	$	274,629	$	(24,422)	$	1,371,752	$	(80,709)

	December 31, 2021
	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	$	14,488	$	(236)	$	—	$	—	$	14,488	$	(236)
Mortgage-backed securities and collateralized mortgage obligations	$	820,746	$	(11,892)	$	62,407	$	(1,381)	$	883,153	$	(13,273)
Corporate debt securities	29,221		(671)		4,705		(295)		33,926		(966)
	$	864,455	$	(12,799)	$	67,112	$	(1,676)	$	931,567	$	(14,475)

Debt Securities, Available-for-sale, Allowance for Credit Loss

The following table presents the activity in the allowance for credit losses on debt securities available for sale for the three months ended March 31, 2022:

	Three Months Ended March 31, 2022
	(In thousands)
Allowance for Credit Losses:
Balance at December 31, 2021	$	—
Impact of adopting ASU 2016-13 (CECL) effective January 1, 2022	490,000
Provision for credit losses	654,000
Balance at March 31, 2022	$	1,144,000