Securities (Tables)

6 Months Ended

Jun. 30, 2021

Investments, Debt and Equity Securities [Abstract]

Summary of Amortized Cost and Fair Value of Securities Available for Sale

The amortized cost, gross unrealized gains and losses and fair value of securities available-for-sale and held-to-maturity at June 30, 2021 and December 31, 2020 are summarized as follows:

	June 30, 2021
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Debt securities available-for-sale
U.S. Treasury securities and obligations of U.S. government agencies	$	7,412	$	439	$	(2)	$	7,849
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	987,402		14,224		(5,906)		995,720
Private mortgage-backed securities and collateralized mortgage obligations	73,469		1,938		(218)		75,189
Collateralized loan obligations	209,835		22		(165)		209,692
Obligations of state and political subdivisions	32,288		2,038		—		34,326
Totals	$	1,310,406	$	18,661	$	(6,291)	$	1,322,776
Debt securities held-to-maturity
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	$	493,467	$	5,697	$	(9,875)	$	489,289
Totals	$	493,467	$	5,697	$	(9,875)	$	489,289

	December 31, 2020
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Debt securities available-for-sale
U.S. Treasury securities and obligations of U.S. government agencies	$	8,250	$	528	$	(1)	$	8,777
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	1,038,437		23,457		(1,240)		1,060,654
Private mortgage-backed securities and collateralized mortgage obligations	89,284		2,131		(210)		91,205
Collateralized loan obligations	202,563		279		(647)		202,195
Obligations of state and political subdivisions	33,005		2,321		—		35,326
Totals	$	1,371,539	$	28,716	$	(2,098)	$	1,398,157
Debt securities held-to-maturity
Mortgage-backed securities of U.S. government-sponsored entities	$	184,484	$	7,818	$	(123)	$	192,179
Totals	$	184,484	$	7,818	$	(123)	$	192,179

Summary of Amortized Cost and Fair Value of Held-to-Maturity Securities

The amortized cost, gross unrealized gains and losses and fair value of securities available-for-sale and held-to-maturity at June 30, 2021 and December 31, 2020 are summarized as follows:

	June 30, 2021
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Debt securities available-for-sale
U.S. Treasury securities and obligations of U.S. government agencies	$	7,412	$	439	$	(2)	$	7,849
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	987,402		14,224		(5,906)		995,720
Private mortgage-backed securities and collateralized mortgage obligations	73,469		1,938		(218)		75,189
Collateralized loan obligations	209,835		22		(165)		209,692
Obligations of state and political subdivisions	32,288		2,038		—		34,326
Totals	$	1,310,406	$	18,661	$	(6,291)	$	1,322,776
Debt securities held-to-maturity
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	$	493,467	$	5,697	$	(9,875)	$	489,289
Totals	$	493,467	$	5,697	$	(9,875)	$	489,289

	December 31, 2020
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Debt securities available-for-sale
U.S. Treasury securities and obligations of U.S. government agencies	$	8,250	$	528	$	(1)	$	8,777
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	1,038,437		23,457		(1,240)		1,060,654
Private mortgage-backed securities and collateralized mortgage obligations	89,284		2,131		(210)		91,205
Collateralized loan obligations	202,563		279		(647)		202,195
Obligations of state and political subdivisions	33,005		2,321		—		35,326
Totals	$	1,371,539	$	28,716	$	(2,098)	$	1,398,157
Debt securities held-to-maturity
Mortgage-backed securities of U.S. government-sponsored entities	$	184,484	$	7,818	$	(123)	$	192,179
Totals	$	184,484	$	7,818	$	(123)	$	192,179

Summary of Investments Classified by Contractual Maturity

Securities not due at a single maturity date are shown separately.

	Held-to-Maturity				Available-for-Sale
(In thousands)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due in less than one year	$	—	$	—	$	400	$	402
Due after one year through five years	—		—		12,316		13,175
Due after five years through ten years	—		—		8,505		8,923
Due after ten years	—		—		18,479		19,675
	—		—		39,700		42,175
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	493,467		489,289		987,402		995,720
Private mortgage-backed securities and collateralized mortgage obligations	—		—		73,469		75,189
Collateralized loan obligations	—		—		209,835		209,692
Totals	$	493,467	$	489,289	$	1,310,406	$	1,322,776

Schedule of Debt Securities in Unrealized Loss Position

The tables below indicate the fair value of available-for-sale debt securities with unrealized losses for which no allowance for credit losses has been recorded.

	June 30, 2021
	Less Than 12 Months				12 Months or Longer				Total
(In thousands)	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
U.S. Treasury securities and obligations of U.S. government agencies	$	—	$	—	$	251	$	(2)	$	251	$	(2)
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	538,907		(5,866)		4,389		(40)		543,296		(5,906)
Private mortgage-backed securities and collateralized mortgage obligations	14,979		(195)		1,738		(23)		16,717		(218)
Collateralized loan obligations	82,191		(108)		9,450		(57)		91,641		(165)
Totals	$	636,077	$	(6,169)	$	15,828	$	(122)	$	651,905	$	(6,291)

	December 31, 2020
	Less Than 12 Months				12 Months or Longer				Total
(In thousands)	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
U.S. Treasury securities and obligations of U.S. government agencies	$	—	$	—	$	256	$	(1)	$	256	$	(1)
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	203,405		(1,218)		569		(22)		203,974		(1,240)
Private mortgage-backed securities and collateralized mortgage obligations	23,997		(210)		—		—		23,997		(210)
Collateralized loan obligations	104,697		(102)		72,513		(545)		177,210		(647)
Totals	$	332,099	$	(1,530)	$	73,338	$	(568)	$	405,437	$	(2,098)