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Investment Securities (Tables)

9 Months Ended

Sep. 30, 2025

Investments, Debt and Equity Securities [Abstract]

Schedule of Available-for-sale Securities Reconciliation

Investment securities include investment securities available for sale and marketable equity securities. The investment securities portfolio consisted of the following at the dates indicated (in thousands):

			September 30, 2025
			Amortized Cost						Gross Unrealized												Carrying Value
									Gains						Losses
Investment securities available for sale:
U.S. Treasury securities			$	175,307					$	1,035					$	(7,625)					$	168,717
U.S. Government agency and sponsored enterprise residential MBS			2,699,845						12,055						(16,398)						2,695,502
U.S. Government agency and sponsored enterprise commercial MBS			571,192						565						(45,032)						526,725
Private label residential MBS and CMOs			2,562,963						2,439						(209,197)						2,356,205
Private label commercial MBS			2,277,909						4,792						(22,321)						2,260,380
Single family real estate-backed securities			229,293						329						(2,541)						227,081
Collateralized loan obligations			988,160						747						(552)						988,355
Non-mortgage asset-backed securities			68,711						249						(1,062)						67,898
State and municipal obligations			111,421						238						(5,894)						105,765
SBA securities			63,554						26						(1,795)						61,785
			$	9,748,355					$	22,475					$	(312,417)					$	9,458,413
Marketable equity securities																					8,669
																					$	9,467,082

			December 31, 2024
			Amortized Cost						Gross Unrealized												Carrying Value
									Gains						Losses
Investment securities available for sale:
U.S. Treasury securities			$	214,796					$	165					$	(12,009)					$	202,952
U.S. Government agency and sponsored enterprise residential MBS			2,672,554						3,607						(26,471)						2,649,690
U.S. Government agency and sponsored enterprise commercial MBS			557,489						156						(61,892)						495,753
Private label residential MBS and CMOs			2,491,033						506						(253,493)						2,238,046
Private label commercial MBS			1,822,881						1,836						(40,688)						1,784,029
Single family real estate-backed securities			335,047						108						(8,074)						327,081
Collateralized loan obligations			1,131,088						1,804						(193)						1,132,699
Non-mortgage asset-backed securities			96,865						144						(2,555)						94,454
State and municipal obligations			110,388						13						(6,391)						104,010
SBA securities			74,900						37						(2,235)						72,702
			$	9,507,041					$	8,376					$	(414,001)					$	9,101,416
Marketable equity securities																					28,828
																					$	9,130,244

Investments Classified by Contractual Maturity Date

At September 30, 2025, contractual maturities of investment securities available for sale, adjusted for anticipated prepayments when applicable, were as follows (in thousands):

			Amortized Cost						Fair Value
Due in one year or less			$	894,192					$	876,890
Due after one year through five years			5,609,431						5,528,183
Due after five years through ten years			2,207,989						2,104,486
Due after ten years			1,036,743						948,854
			$	9,748,355					$	9,458,413

Gain on Investment Securities, net

The following table provides information about gains (losses) on investment securities for the periods indicated (in thousands):

			Three Months Ended September 30,												Nine Months Ended September 30,
			2025						2024						2025						2024
Gross realized gains on investment securities AFS			$	674					$	76					$	2,267					$	501
Gross realized losses on investment securities AFS			(15)						(67)						(170)						(170)
Net realized gain			659						9						2,097						331
Net gain (loss) on marketable equity securities recognized in earnings			(11)						118						(157)						992
Gain on investment securities, net			$	648					$	127					$	1,940					$	1,323

Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value

The following tables present the aggregate fair value and the aggregate amount by which amortized cost exceeded fair value for investment securities available for sale in unrealized loss positions aggregated by investment category and length of time that individual securities had been in continuous unrealized loss positions at the dates indicated (in thousands):

			September 30, 2025
			Less than 12 Months												12 Months or Greater												Total
			Fair Value						Unrealized Losses						Fair Value						Unrealized Losses						Fair Value						Unrealized Losses
U.S. Treasury securities			$	25,205					$	(219)					$	97,412					$	(7,406)					$	122,617					$	(7,625)
U.S. Government agency and sponsored enterprise residential MBS			86,533						(557)						734,596						(15,841)						821,129						(16,398)
U.S. Government agency and sponsored enterprise commercial MBS			24,643						(116)						438,933						(44,916)						463,576						(45,032)
Private label residential MBS and CMOs			18,006						(197)						1,943,761						(209,000)						1,961,767						(209,197)
Private label commercial MBS			182,380						(392)						488,270						(21,929)						670,650						(22,321)
Single family real estate-backed securities			—						—						152,836						(2,541)						152,836						(2,541)
Collateralized loan obligations			186,929						(454)						30,402						(98)						217,331						(552)
Non-mortgage asset-backed securities			—						—						15,678						(1,062)						15,678						(1,062)
State and municipal obligations			1,190						(5)						51,780						(5,889)						52,970						(5,894)
SBA securities			—						—						58,136						(1,795)						58,136						(1,795)
			$	524,886					$	(1,940)					$	4,011,804					$	(310,477)					$	4,536,690					$	(312,417)

			December 31, 2024
			Less than 12 Months												12 Months or Greater												Total
			Fair Value						Unrealized Losses						Fair Value						Unrealized Losses						Fair Value						Unrealized Losses
U.S. Treasury securities			$	126,710					$	(3,195)					$	40,791					$	(8,814)					$	167,501					$	(12,009)
U.S. Government agency and sponsored enterprise residential MBS			895,759						(5,474)						936,106						(20,997)						1,831,865						(26,471)
U.S. Government agency and sponsored enterprise commercial MBS			55,431						(1,545)						394,735						(60,347)						450,166						(61,892)
Private label residential MBS and CMOs			147,700						(954)						2,040,335						(252,539)						2,188,035						(253,493)
Private label commercial MBS			44,000						(302)						1,199,150						(40,386)						1,243,150						(40,688)
Single family real estate-backed securities			—						—						301,973						(8,074)						301,973						(8,074)
Collateralized loan obligations			336,924						(189)						7,726						(4)						344,650						(193)
Non-mortgage asset-backed securities			—						—						71,789						(2,555)						71,789						(2,555)
State and municipal obligations			15,765						(148)						54,820						(6,243)						70,585						(6,391)
SBA securities			—						—						67,880						(2,235)						67,880						(2,235)
			$	1,622,289					$	(11,807)					$	5,115,305					$	(402,194)					$	6,737,594					$	(414,001)

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