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Investment Securities (Tables)

6 Months Ended

Jun. 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):

			June 30, 2025
			Amortized Cost						Gross Unrealized												Carrying Value
									Gains						Losses
Investment securities available for sale:
U.S. Treasury securities			$	149,875					$	998					$	(8,304)					$	142,569
U.S. Government agency and sponsored enterprise residential MBS			2,721,476						10,330						(19,268)						2,712,538
U.S. Government agency and sponsored enterprise commercial MBS			548,402						450						(48,527)						500,325
Private label residential MBS and CMOs			2,586,509						1,502						(226,507)						2,361,504
Private label commercial MBS			2,119,814						2,902						(27,677)						2,095,039
Single family real estate-backed securities			207,306						240						(4,193)						203,353
Collateralized loan obligations			1,119,184						690						(1,043)						1,118,831
Non-mortgage asset-backed securities			91,483						6						(1,699)						89,790
State and municipal obligations			111,897						51						(8,074)						103,874
SBA securities			66,443						27						(1,901)						64,569
			$	9,722,389					$	17,196					$	(347,193)					$	9,392,392
Marketable equity securities																					8,679
																					$	9,401,071

			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 June 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			$	801,840					$	781,538
Due after one year through five years			5,300,383						5,211,984
Due after five years through ten years			2,429,925						2,304,295
Due after ten years			1,190,241						1,094,575
			$	9,722,389					$	9,392,392

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 June 30,												Six Months Ended June 30,
			2025						2024						2025						2024
Gross realized gains on investment securities AFS			$	731					$	398					$	1,593					$	425
Gross realized losses on investment securities AFS			(118)						(48)						(155)						(103)
Net realized gain			613						350						1,438						322
Net gain (loss) on marketable equity securities recognized in earnings			(266)						71						(147)						874
Gain on investment securities, net			$	347					$	421					$	1,291					$	1,196

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):

			June 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			$	53,724					$	(1,442)					$	42,776					$	(6,862)					$	96,500					$	(8,304)
U.S. Government agency and sponsored enterprise residential MBS			334,189						(2,077)						711,375						(17,191)						1,045,564						(19,268)
U.S. Government agency and sponsored enterprise commercial MBS			37,967						(376)						401,394						(48,151)						439,361						(48,527)
Private label residential MBS and CMOs			201,978						(1,503)						1,967,841						(225,004)						2,169,819						(226,507)
Private label commercial MBS			440,202						(1,056)						633,038						(26,621)						1,073,240						(27,677)
Single family real estate-backed securities			—						—						156,151						(4,193)						156,151						(4,193)
Collateralized loan obligations			573,567						(1,043)						—						—						573,567						(1,043)
Non-mortgage asset-backed securities			—						—						68,714						(1,699)						68,714						(1,699)
State and municipal obligations			15,813						(72)						51,218						(8,002)						67,031						(8,074)
SBA securities			—						—						60,862						(1,901)						60,862						(1,901)
			$	1,657,440					$	(7,569)					$	4,093,369					$	(339,624)					$	5,750,809					$	(347,193)

			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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