Securities (Tables)

3 Months Ended

Mar. 31, 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 March 31, 2021 and December 31, 2020 are summarized as follows:

	March 31, 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	$	7,686	$	334	$	(2)	$	8,018
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	746,409		14,584		(6,774)		754,219
Private mortgage-backed securities and collateralized mortgage obligations	80,156		1,989		(261)		81,884
Collateralized loan obligations	172,392		239		(160)		172,471
Obligations of state and political subdivisions	32,914		1,943		(53)		34,804
Totals	$	1,039,557	$	19,089	$	(7,250)	$	1,051,396
Debt securities held-to-maturity
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	$	512,307	$	5,539	$	(17,126)	$	500,720
Totals	$	512,307	$	5,539	$	(17,126)	$	500,720

	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 March 31, 2021 and December 31, 2020 are summarized as follows:

	March 31, 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	$	7,686	$	334	$	(2)	$	8,018
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	746,409		14,584		(6,774)		754,219
Private mortgage-backed securities and collateralized mortgage obligations	80,156		1,989		(261)		81,884
Collateralized loan obligations	172,392		239		(160)		172,471
Obligations of state and political subdivisions	32,914		1,943		(53)		34,804
Totals	$	1,039,557	$	19,089	$	(7,250)	$	1,051,396
Debt securities held-to-maturity
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	$	512,307	$	5,539	$	(17,126)	$	500,720
Totals	$	512,307	$	5,539	$	(17,126)	$	500,720

	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	$	—	$	—	$	435	$	437
Due after one year through five years	—		—		12,400		13,310
Due after five years through ten years	—		—		8,113		8,464
Due after ten years	—		—		19,652		20,611
	—		—		40,600		42,822
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	512,307		500,720		746,409		754,219
Private mortgage-backed securities and collateralized mortgage obligations	—		—		80,156		81,884
Collateralized loan obligations	—		—		172,392		172,471
Totals	$	512,307	$	500,720	$	1,039,557	$	1,051,396

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.

	March 31, 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	$	—	$	—	$	253	$	(2)	$	253	$	(2)
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities	314,851		(6,725)		4,888		(49)		319,739		(6,774)
Private mortgage-backed securities and collateralized mortgage obligations	18,752		(236)		2,029		(25)		20,781		(261)
Collateralized loan obligations	125,035		(88)		28,435		(72)		153,470		(160)
Obligations of state and political subdivisions	4,982		(53)		—		—		4,982		(53)
Totals	$	463,620	$	(7,102)	$	35,605	$	(148)	$	499,225	$	(7,250)

	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)