Investment Securities (Tables)

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Schedule of Available-for-sale Securities Reconciliation

The following table presents amortized cost, gross unrealized gains and losses, and fair values of securities available-for-sale as of the dates indicated:

	December 31, 2023
			Allowance				Gross		Gross
	Amortized		for Credit		Net Carrying		Unrealized		Unrealized		Fair
Security Type	Cost		Losses		Amount		Gains		Losses		Value
	(In thousands)
Agency residential MBS	$	1,388,801	$	—	$	1,388,801	$	—	$	(201,192)	$	1,187,609
U.S. Treasury securities	4,965		—		4,965		3		—		4,968
Agency commercial MBS	268,639		—		268,639		—		(15,333)		253,306
Agency residential CMOs	320,984		—		320,984		—		(36,650)		284,334
Municipal securities	29,192		—		29,192		—		(1,109)		28,083
Corporate debt securities	327,426		(199)		327,227		259		(60,254)		267,232
Private label residential CMOs	193,071		—		193,071		—		(34,659)		158,412
Collateralized loan obligations	109,168		—		109,168		—		(752)		108,416
Private label commercial MBS	22,126		—		22,126		—		(1,313)		20,813
Asset-backed securities	20,241		—		20,241		—		(289)		19,952
SBA securities	14,642		—		14,642		—		(903)		13,739
Total	$	2,699,255	$	(199)	$	2,699,056	$	262	$	(352,454)	$	2,346,864

    

	December 31, 2022
			Allowance				Gross		Gross
	Amortized		for Credit		Net Carrying		Unrealized		Unrealized		Fair
Security Type	Cost		Losses		Amount		Gains		Losses		Value
	(In thousands)
Agency residential MBS	$	2,685,038	$	—	$	2,685,038	$	—	$	(442,996)	$	2,242,042
U.S. Treasury securities	771,145		—		771,145		—		(101,075)		670,070
Agency commercial MBS	549,492		—		549,492		—		(61,886)		487,606
Agency residential CMOs	517,174		—		517,174		—		(60,111)		457,063
Municipal securities	399,724		—		399,724		—		(60,398)		339,326
Corporate debt securities	344,767		—		344,767		6		(32,868)		311,905
Private label residential CMOs	207,123		—		207,123		—		(40,399)		166,724
Collateralized loan obligations	109,159		—		109,159		—		(6,898)		102,261
Private label commercial MBS	28,903		—		28,903		—		(2,076)		26,827
Asset-backed securities	23,568		—		23,568		—		(1,155)		22,413
SBA securities	18,524		—		18,524		—		(1,274)		17,250
Total	$	5,654,617	$	—	$	5,654,617	$	6	$	(811,136)	$	4,843,487

Schedule of Realized Gain (Loss)

The following table presents the amortized cost of securities sold with related gross realized gains, gross realized losses, and net realized (losses) gains for the years indicated:

	Year Ended December 31,
Sales of Securities Available-for-Sale	2023		2022		2021
	(In thousands)
Amortized cost of securities sold	$	3,470,424	$	2,063,415	$	365,733
Gross realized gains	$	—	$	6,032	$	1,680
Gross realized losses	(442,413)		(56,353)		(65)
Net realized (losses) gains	$	(442,413)	$	(50,321)	$	1,615

Unrealized losses on investment securities

Unrealized Losses on Securities Available-for-Sale

The following tables present the gross unrealized losses and fair values of securities available-for-sale that were in unrealized loss positions as of the dates indicated:

	December 31, 2023
	Less Than 12 Months				12 Months or More				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
Security Type	Value		Losses		Value		Losses		Value		Losses
	(In thousands)
Agency residential MBS	$	—	$	—	$	1,187,609	$	(201,192)	$	1,187,609	$	(201,192)
U.S. Treasury securities	—		—		—		—		—		—
Agency commercial MBS	—		—		253,306		(15,333)		253,306		(15,333)
Agency residential CMOs	—		—		284,334		(36,650)		284,334		(36,650)
Municipal securities	—		—		28,083		(1,109)		28,083		(1,109)
Corporate debt securities	—		—		265,431		(60,254)		265,431		(60,254)
Private label residential CMOs	—		—		158,412		(34,659)		158,412		(34,659)
Collateralized loan obligations	—		—		66,886		(752)		66,886		(752)
Private label commercial MBS	—		—		20,813		(1,313)		20,813		(1,313)
Asset-backed securities	—		—		19,952		(289)		19,952		(289)
SBA securities	—		—		13,739		(903)		13,739		(903)
Total	$	—	$	—	$	2,298,565	$	(352,454)	$	2,298,565	$	(352,454)

	December 31, 2022
	Less Than 12 Months				12 Months or More				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
Security Type	Value		Losses		Value		Losses		Value		Losses
	(In thousands)
Agency residential MBS	$	52,556	$	(6,193)	$	2,189,485	$	(436,803)	$	2,242,041	$	(442,996)
U.S. Treasury securities	4,972		(26)		665,098		(101,049)		670,070		(101,075)
Agency commercial MBS	316,892		(31,139)		170,714		(30,747)		487,606		(61,886)
Agency residential CMOs	245,755		(22,748)		211,309		(37,363)		457,064		(60,111)
Municipal securities	37,380		(3,129)		298,266		(57,269)		335,646		(60,398)
Corporate debt securities	302,643		(32,124)		4,256		(744)		306,899		(32,868)
Private label residential CMOs	19,261		(1,294)		147,464		(39,105)		166,725		(40,399)
Collateralized loan obligations	27,704		(1,818)		74,558		(5,080)		102,262		(6,898)
Private label commercial MBS	10,204		(508)		16,623		(1,568)		26,827		(2,076)
Asset-backed securities	22,413		(1,155)		—		—		22,413		(1,155)
SBA securities	17,250		(1,274)		—		—		17,250		(1,274)
Total	$	1,057,030	$	(101,408)	$	3,777,773	$	(709,728)	$	4,834,803	$	(811,136)

Investments Classified by Contractual Maturity Date, Available-For-Sale

The following tables present the contractual maturities of our available-for-sale securities portfolio based on amortized cost and fair value as of the date indicated:

	December 31, 2023
			Due After		Due After
	Due		One Year		Five Years		Due
	Within		Through		Through		After
Security Type	One Year		Five Years		Ten Years		Ten Years		Total
	(In thousands)
Amortized Cost:
Agency residential MBS	$	—	$	—	$	—	$	1,388,801	$	1,388,801
U.S. Treasury securities	4,965		—		—		—		4,965
Agency commercial MBS	—		165,420		85,712		17,507		268,639
Agency residential CMOs	—		36,183		15,135		269,666		320,984
Municipal securities	—		7,341		21,851		—		29,192
Corporate debt securities	—		5,000		322,426		—		327,426
Private label residential CMOs	—		—		—		193,071		193,071
Collateralized loan obligations	—		—		80,330		28,838		109,168
Private label commercial MBS	—		—		1,325		20,801		22,126
Asset-backed securities	—		—		—		20,241		20,241
SBA securities	—		2,643		—		11,999		14,642
Total	$	4,965	$	216,587	$	526,779	$	1,950,924	$	2,699,255

	December 31, 2023
			Due After		Due After
	Due		One Year		Five Years		Due
	Within		Through		Through		After
Security Type	One Year		Five Years		Ten Years		Ten Years		Total
	(In thousands)
Fair Value:
Agency residential MBS	$	—	$	—	$	—	$	1,187,609	$	1,187,609
U.S. Treasury securities	4,968		—		—		—		4,968
Agency commercial MBS	—		157,087		79,600		16,619		253,306
Agency residential CMOs	—		33,480		13,912		236,942		284,334
Municipal securities	—		6,991		21,092		—		28,083
Corporate debt securities	—		4,850		262,382		—		267,232
Private label residential CMOs	—		—		—		158,412		158,412
Collateralized loan obligations	—		—		79,867		28,549		108,416
Private label commercial MBS	—		—		1,283		19,530		20,813
Asset-backed securities	—		—		—		19,952		19,952
SBA securities	—		2,534		—		11,205		13,739
Total	$	4,968	$	204,942	$	458,136	$	1,678,818	$	2,346,864

Debt Securities, Held-to-maturity

The following table presents amortized cost, allowance for credit losses, gross unrealized gains and losses, and fair values of securities held-to-maturity as of the dates indicated:

	December 31, 2023
			Allowance
			for		Net		Gross		Gross
	Amortized		Credit		Carrying		Unrealized		Unrealized		Fair
Security Type	Cost		Losses		Amount		Gains		Losses		Value
	(In thousands)
Municipal securities	$	1,247,310	$	(140)	$	1,247,170	$	1,760	$	(28,170)	$	1,220,760
Agency commercial MBS	433,827		—		433,827		—		(30,665)		403,162
Private label commercial MBS	350,493		—		350,493		—		(29,289)		321,204
U.S. Treasury securities	187,033		—		187,033		—		(11,454)		175,579
Corporate debt securities	70,128		(1,360)		68,768		—		(21,157)		47,611
Total (1)	$	2,288,791	$	(1,500)	$	2,287,291	$	1,760	$	(120,735)	$	2,168,316

__________________________

(1)    Excludes accrued interest receivable of $13.4 million at December 31, 2023 which is recorded in "Other assets" on the consolidated balance sheets.

	December 31, 2022
			Allowance
			for		Net		Gross		Gross
	Amortized		Credit		Carrying		Unrealized		Unrealized		Fair
Security Type	Cost		Losses		Amount		Gains		Losses		Value
	(In thousands)
Municipal securities	$	1,243,443	$	(140)	$	1,243,303	$	8	$	(77,526)	$	1,165,785
Agency commercial MBS	427,411		—		427,411		—		(34,287)		393,124
Private label commercial MBS	345,825		—		345,825		—		(26,027)		319,798
U.S. Treasury securities	184,162		—		184,162		—		(12,462)		171,700
Corporate debt securities	69,794		(1,360)		68,434		—		(8,369)		60,065
Total (1)	$	2,270,635	$	(1,500)	$	2,269,135	$	8	$	(158,671)	$	2,110,472

__________________________

(1)    Excludes accrued interest receivable of $13.5 million at December 31, 2022 which is recorded in "Other assets" on the consolidated balance sheets.

Debt Securities, Held-to-maturity, Allowance for Credit Loss

The following table presents the changes by major security type in our allowance for credit losses on securities held-to-maturity for the years indicated:

	Year Ended December 31, 2023
	Allowance for		Provision						Allowance for
	Credit Losses,		for						Credit Losses,
	Beginning		Credit						End of
Security Type	of Period		Losses		Charge-offs		Recoveries		Period
	(In thousands)
Municipal securities	$	140	$	—	$	—	$	—	$	140
Corporate debt securities	1,360		—		—		—		1,360
Total	$	1,500	$	—	$	—	$	—	$	1,500
	Year Ended December 31, 2022
	Allowance for		Provision						Allowance for
	Credit Losses,		for						Credit Losses,
	Beginning		Credit						End of
Security Type	of Period		Losses		Charge-offs		Recoveries		Period
	(In thousands)
Municipal securities	$	—	$	140	$	—	$	—	$	140
Corporate debt securities	—		1,360		—		—		1,360
Total	$	—	$	1,500	$	—	$	—	$	1,500

Debt Securities, Held-to-maturity, Credit Quality Indicator

The Company uses S&P, Moody's, Fitch, Kroll, and Egan Jones ratings as the credit quality indicators for its held-to-maturity securities. The following table presents our securities held-to-maturity portfolio by the lowest available credit rating as of the dates indicated:

	December 31, 2023
Security Type	AAA		AA+		AA		AA-		A		BBB		NR		Total
	(In thousands)
Amortized Cost:
Municipal securities	$	564,127	$	397,542	$	167,905	$	86,243	$	1,787	$	—	$	17,699	$	1,247,310
Agency commercial MBS	—		433,827		—		—		—		—		—		433,827
Private label commercial MBS	350,493		—		—		—		—		—		—		350,493
U.S. Treasury securities	—		187,033		—		—		—		—		—		187,033
Corporate debt securities	—		—		—		—		—		44,371		25,757		70,128
Total	$	914,620	$	1,018,402	$	167,905	$	86,243	$	1,787	$	44,371	$	43,456	$	2,288,791

	December 31, 2022
Security Type	AAA		AA+		AA		AA-		A		A-		BBB		NR		Total
	(In thousands)
Amortized Cost:
Municipal securities	$	568,674	$	385,990	$	173,751	$	95,471	$	1,901	$	—	$	—	$	17,656	$	1,243,443
Agency commercial MBS	—		427,411		—		—		—		—		—		—		427,411
Private label commercial MBS	345,825		—		—		—		—		—		—		—		345,825
U.S. Treasury securities	—		184,162		—		—		—		—		—		—		184,162
Corporate debt securities	—		—		—		—		—		23,244		20,999		25,551		69,794
Total	$	914,499	$	997,563	$	173,751	$	95,471	$	1,901	$	23,244	$	20,999	$	43,207	$	2,270,635

Investment Securities Classified by Contractual Maturities Date - Held-to-Maturity

The following table presents the contractual maturities of our securities held-to-maturity portfolio based on amortized cost and fair value as of the date indicated:

	December 31, 2023
			Due After		Due After
	Due		One Year		Five Years		Due
	Within		Through		Through		After
Security Type	One Year		Five Years		Ten Years		Ten Years		Total
	(In thousands)
Amortized Cost:
Municipal securities	$	—	$	—	$	390,724	$	856,586	$	1,247,310
Agency commercial MBS	—		—		433,827		—		433,827
Private label commercial MBS	—		—		36,407		314,086		350,493
U.S. Treasury securities	—		—		187,033		—		187,033
Corporate debt securities	—		—		10,191		59,937		70,128
Total	$	—	$	—	$	1,058,182	$	1,230,609	$	2,288,791

	December 31, 2023
			Due After		Due After
	Due		One Year		Five Years		Due
	Within		Through		Through		After
Security Type	One Year		Five Years		Ten Years		Ten Years		Total
	(In thousands)
Fair Value:
Municipal securities	$	—	$	—	$	375,009	$	845,751	$	1,220,760
Agency commercial MBS	—		—		403,162		—		403,162
Private label commercial MBS	—		—		34,324		286,880		321,204
U.S. Treasury securities	—		—		175,579		—		175,579
Corporate debt securities	—		—		8,766		38,845		47,611
Total	$	—	$	—	$	996,840	$	1,171,476	$	2,168,316

Investment Income

The following table presents the composition of our interest income on investment securities for the years indicated:

	Year Ended December 31,
	2023		2022		2021
	(In thousands)
Taxable interest	$	150,710	$	179,496	$	118,561
Non-taxable interest	19,479		28,936		33,916
Dividend income	4,807		1,319		991
Total interest income on investment securities	$	174,996	$	209,751	$	153,468