The following tables detail the amortized cost, allowance for credit losses and the estimated fair value of the Company's investments in available-for-sale and held-to-maturity debt securities. None of the Company's investments in debt securities are classified as trading.


	June 30, 2026
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Allowance for Credit Losses		Fair Value
Available-for-Sale Debt Securities
Collateralized mortgage obligations (CMO)	$	455,189	$	237	$	73,447	$	—	$	381,979
Fannie Mae (FNMA) mortgage-backed securities (MBS)	3,436,640		1,288		401,338		—		3,036,590
Freddie Mac (FHLMC) MBS	157,384		34		8,683		—		148,735
Ginnie Mae (GNMA) MBS	91,106		227		2,917		—		88,416
Government-sponsored enterprises (GSE) agency notes	219,012		—		33,724		—		185,288
	$	4,359,331	$	1,786	$	520,109	$	—	$	3,841,008
Held-to-Maturity Debt Securities(1)
FNMA MBS	$	766,440	$	—	$	97,327	$	—	$	669,113
State and political subdivisions	176,857		580		714		5		176,718

	$	943,297	$	580	$	98,041	$	5	$	845,831

(1)Held-to-maturity securities transferred from available-for-sale are included in held-to-maturity at fair value basis at the time of transfer. The amortized cost of transferred held-to-maturity securities included net unrealized losses of $75.8 million at June 30, 2026, which are offset in Accumulated other comprehensive loss. At the time of transfer, there was no allowance for credit loss on the available-for-sale securities. Subsequent to transfer, the securities were evaluated for credit loss.


	December 31, 2025
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Allowance for Credit Losses		Fair Value
Available-for-Sale Debt Securities
CMO	$	476,409	$	416	$	71,679	$	—	$	405,146
FNMA MBS	3,167,210		2,289		384,092		—		2,785,407
FHLMC MBS	123,979		68		7,542		—		116,505
GNMA MBS	49,804		59		2,480		—		47,383
GSE agency notes	220,298		—		32,493		—		187,805
	$	4,037,700	$	2,832	$	498,286	$	—	$	3,542,246
Held-to-Maturity Debt Securities(1)
FNMA MBS	$	788,439	$	—	$	89,936	$	—	$	698,503
State and political subdivisions	179,897		1,157		486		5		180,563

	$	968,336	$	1,157	$	90,422	$	5	$	879,066

(1)Held-to-maturity securities transferred from available-for-sale are included in held-to-maturity at fair value at the time of transfer. The amortized cost of transferred held-to-maturity securities included net unrealized losses of $83.4 million at December 31, 2025, which are offset in Accumulated other comprehensive loss. At the time of transfer, there was no allowance for credit loss on the available-for-sale securities. Subsequent to transfer, the securities were evaluated for credit loss.

The scheduled maturities of available-for-sale debt securities at June 30, 2026 and December 31, 2025 are presented in the table below:


	Available-for-Sale
	Amortized		Fair
(Dollars in thousands)	Cost		Value
June 30, 2026 (1)
Within one year	$	307,598	$	306,874
After one year but within five years	247,738		233,568
After five years but within ten years	564,189		503,230
After ten years	3,239,805		2,797,335
	$	4,359,331	$	3,841,008
December 31, 2025 (1)
Within one year	$	46,226	$	45,836
After one year but within five years	219,281		208,380
After five years but within ten years	471,231		422,496
After ten years	3,300,962		2,865,534
	$	4,037,700	$	3,542,246

As of June 30, 2026, the Company’s available-for-sale investment securities consisted of 1,071 securities, 1,003 of which were in an unrealized loss position, and substantially all of the Company's available-for-sale investment securities were mortgage-backed securities or collateral mortgage obligations which were issued or guaranteed by U.S. government-sponsored entities and agencies. As of June 30, 2026 and December 31, 2025, there were no holdings of securities of any one issuer, other than the U.S. government and its agencies, in an amount greater than 10% of shareholders’ equity.


	Held-to-Maturity
	Amortized		Fair
(Dollars in thousands)	Cost		Value
June 30, 2026 (1)
Within one year	$	2,650	$	2,645
After one year but within five years	19,941		19,932
After five years but within ten years	78,950		79,069
After ten years	841,756		744,185
	$	943,297	$	845,831
December 31, 2025 (1)
Within one year	$	1,920	$	1,918
After one year but within five years	21,180		21,166
After five years but within ten years	69,374		69,851
After ten years	875,862		786,131
	$	968,336	$	879,066

MBS may have expected maturities that differ from their contractual maturities. These differences arise because issuers may have the right to call securities and borrowers may have the right to prepay obligations with or without prepayment penalty.

The held-to-maturity debt securities are not collateral-dependent securities as these are general obligation bonds issued by cities, states, counties, or other local governments, and government-sponsored MBS.

Investment securities with fair market values aggregating $3.6 billion and $4.1 billion were pledged as collateral for investment sweep repurchase agreements, municipal deposits, and other obligations as of June 30, 2026 and December 31, 2025, respectively.

As of June 30, 2026 and December 31, 2025, the Company's debt securities portfolio had remaining unamortized premiums of $36.7 million and $40.4 million, respectively, and unaccreted discounts of $34.3 million and $17.4 million, respectively.

For debt securities in an unrealized loss position, the table below shows the gross unrealized losses and fair value by investment category and length of time that individual debt securities were in a continuous unrealized loss position at June 30, 2026.


	Duration of Unrealized Loss Position
	Less than 12 months				12 months or longer				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
(Dollars in thousands)	Value		Loss		Value		Loss		Value		Loss
Available-for-sale debt securities:
CMO	$	13,431	$	256	$	358,632	$	73,191	$	372,063	$	73,447
FNMA MBS	457,986		6,020		2,390,367		395,318		2,848,353		401,338
FHLMC MBS	34,840		287		99,009		8,396		133,849		8,683
GNMA MBS	19,424		271		30,010		2,646		49,434		2,917
GSE agency notes	—		—		185,289		33,724		185,289		33,724
	$	525,681	$	6,834	$	3,063,307	$	513,275	$	3,588,988	$	520,109


	Duration of Unrealized Loss Position
	Less than 12 months				12 months or longer				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
(Dollars in thousands)	Value		Loss		Value		Loss		Value		Loss
Available-for-sale debt securities:
CMO	$	—	$	—	$	394,776	$	71,679	$	394,776	$	71,679
FNMA MBS	68,311		353		2,551,281		383,739		2,619,592		384,092
FHLMC MBS	7,978		58		103,510		7,484		111,488		7,542
GNMA MBS	4,323		93		34,290		2,387		38,613		2,480
GSE agency notes	—		—		187,805		32,493		187,805		32,493
	$	80,612	$	504	$	3,271,662	$	497,782	$	3,352,274	$	498,286

The Company does not have the intent to sell, nor is it more likely than not it will be required to sell these securities before it is able to recover the amortized cost basis. The unrealized losses are the result of changes in market interest rates subsequent to purchase, not credit loss, as these are highly rated agency securities with no expected credit loss, in the event of a default. As a result, there is no allowance for credit losses recorded for available-for-sale debt securities as of June 30, 2026.

At June 30, 2026 and December 31, 2025, held-to-maturity debt securities had an amortized cost basis of $943.3 million and $968.3 million, respectively. The held-to-maturity debt security portfolio primarily consists of mortgage-backed securities which were issued or guaranteed by U.S. government-sponsored entities and agencies and highly rated municipal bonds. The Company monitors credit quality of its non-government and non-agency securities through credit ratings. The following table summarizes the amortized cost of debt securities held-to-maturity as of June 30, 2026, aggregated by credit quality indicator:


(Dollars in thousands)	FNMA MBS		State and political subdivisions
A+ rated or higher	$	—	$	176,857
Not rated	766,440		—
Ending balance	$	766,440	$	176,857


(Dollars in thousands)	FNMA MBS		State and political subdivisions
A+ rated or higher	$	—	$	179,897
Not rated	788,439		—
Ending balance	$	788,439	$	179,897

The Company reviewed its held-to-maturity debt securities by major security type for potential credit losses. There was no activity in the allowance for credit losses for FNMA MBS debt securities for the six months ended June 30, 2026 and 2025. See Note 6 for information on the activity in the allowance for credit losses for state and political subdivisions debt securities for the three and six months ended June 30, 2026 and 2025.

Accrued interest receivable of $3.4 million as of June 30, 2026 and December 31, 2025 for held-to-maturity debt securities were excluded from the evaluation of allowance for credit losses. There were no nonaccrual or past due held-to-maturity debt securities as of June 30, 2026 and December 31, 2025.

During the three and six months ended June 30, 2026, the Company recognized an impairment loss of $4.1 million related to one of our equity investments recorded within Unrealized (loss) gain on equity investments, net in the unaudited Consolidated Statements of Income. The Company also recognized realized gains of $0.2 million related to our equity investments for the three and six months ended June 30, 2026. The Company recognized realized gains of less than $0.1 million related to our equity investments for the three and six months ended June 30, 2025.