Held-to-maturity (“HTM”) securities, which include any security for which the Company has both the positive intent and ability to hold until maturity, are carried at historical cost adjusted for amortization of premiums and accretion of discounts. Premiums and discounts are amortized and accreted, respectively, to interest income using the constant effective yield method over the security’s estimated life. Prepayments are anticipated for mortgage-backed and SBA securities. Premiums on callable securities are amortized to their earliest call date.

Available-for-sale (“AFS”) securities, which include any security for which the Company has no immediate plan to sell but which may be sold in the future, are carried at fair value. Realized gains and losses, based on specifically identified amortized cost of the individual security, are included in other income. Unrealized gains and losses are recorded, net of related income tax effects, in stockholders’ equity, further discussed below. Premiums and discounts are amortized and accreted, respectively, to interest income using the constant effective yield method over the estimated life of the security. Prepayments are anticipated for mortgage-backed and SBA securities. Premiums on callable securities are amortized to their earliest call date.

Assets held in trading accounts, comprised of U.S. Treasury securities, are purchased with the intent of selling in the near term. Trading securities are carried at fair value with gains and losses included in other income.

During the third quarter of 2025, the Company and its subsidiaries initiated and completed steps taken to reposition the Company’s consolidated balance sheet and reclassified approximately $3.59 billion in HTM investment securities to AFS investment securities. Subsequently, the Company sold approximately $3.16 billion in amortized cost basis of AFS securities (including certain of those previously classified as HTM). The sale of investment securities resulted in a realized, after-tax ordinary loss of $625.6 million (based on actual tax rate of 21.946%).

During the quarters ended June 30, 2022 and September 30, 2021, the Company transferred, at fair value, $1.99 billion and $500.8 million, respectively, of securities from the AFS portfolio to the HTM portfolio. No gains or losses on these securities were recognized at the time of transfer. During the balance sheet repositioning that occurred during 2025, the remaining securities were transferred out of the HTM portfolio to the AFS portfolio at fair value and either subsequently sold or maintained within the AFS portfolio.


(In thousands)	Amortized Cost		Allowance for Credit Losses		Gross Unrealized Gains		Gross Unrealized (Losses)		Estimated Fair Value
Available-for-sale

March 31, 2026

U.S. Government agencies	$	46,897	$	—	$	5	$	(573)	$	46,329
Mortgage-backed securities	2,317,158		—		2,096		(190,522)		2,128,732
State and political subdivisions	1,040,398		—		29		(201,547)		838,880
Other securities	143,534		—		67		(5,256)		138,345
Total AFS	$	3,547,987	$	—	$	2,197	$	(397,898)	$	3,152,286

December 31, 2025

U.S. Government agencies	$	47,786	$	—	$	6	$	(620)	$	47,172
Mortgage-backed securities	2,385,646		—		6,072		(189,760)		2,201,958
State and political subdivisions	1,046,121		—		42		(187,092)		859,071
Other securities	163,256		—		209		(5,445)		158,020
Total AFS	$	3,642,809	$	—	$	6,329	$	(382,917)	$	3,266,221

As of March 31, 2026, AFS MBS consisted of $575.7 million and $1.55 billion of commercial MBS and residential MBS, respectively. As of December 31, 2025, AFS MBS consisted of $597.4 million and $1.60 billion of commercial MBS and residential MBS, respectively.

Accrued interest receivable on AFS securities at March 31, 2026 was $20.8 million, and is included in interest receivable on the consolidated balance sheet. The Company has made the election to exclude all accrued interest receivable from securities from the estimate of credit losses.

The following table summarizes the Company’s AFS investments in an unrealized loss position for which an allowance for credit loss has not been recorded as of March 31, 2026 and December 31, 2025, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position:


	Less Than 12 Months				12 Months or More				Total
(In thousands)	Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses
Available-for-sale
March 31, 2026

U.S. Government agencies	$	1,366	$	(1)	$	43,816	$	(572)	$	45,182	$	(573)
Mortgage-backed securities	42,374		(441)		1,608,061		(190,081)		1,650,435		(190,522)
State and political subdivisions	15,025		(1,070)		802,113		(200,477)		817,138		(201,547)
Other securities	2,000		(1)		89,321		(5,255)		91,321		(5,256)
Total AFS	$	60,765	$	(1,513)	$	2,543,311	$	(396,385)	$	2,604,076	$	(397,898)

December 31, 2025

U.S. Government agencies	$	2,247	$	(17)	$	43,767	$	(603)	$	46,014	$	(620)
Mortgage-backed securities	15,305		(74)		1,672,723		(189,686)		1,688,028		(189,760)
State and political subdivisions	5,757		(969)		824,265		(186,123)		830,022		(187,092)
Other securities	—		—		96,176		(5,445)		96,176		(5,445)
Total AFS	$	23,309	$	(1,060)	$	2,636,931	$	(381,857)	$	2,660,240	$	(382,917)

As of March 31, 2026, the Company’s investment portfolio included $3.15 billion of AFS securities, of which $2.60 billion, or 82.6%, were in an unrealized loss position that were not deemed to have credit losses. A portion of the unrealized losses were related to the Company’s MBS, which are issued and guaranteed by U.S. government-sponsored entities and agencies, and the Company’s state and political subdivision securities, specifically investments in insured fixed rate municipal bonds for which the issuers continue to make timely principal and interest payments under the contractual terms of the securities.

Furthermore, the decline in fair value for each of the above AFS securities is attributable to the rates for those investments yielding less than current market rates. Management does not believe any of the securities are impaired due to reasons of credit quality. Management believes the declines in fair value for the securities are temporary. Management does not have the immediate intent to sell the securities, and management believes the accounting standard of “more likely than not” has not been met regarding whether the Company would be required to sell any of the AFS securities before recovery of amortized cost.

All MBS held by the Company are issued by U.S. government-sponsored entities and agencies. These securities are either explicitly or implicitly guaranteed by the U.S. government, highly rated by major rating agencies and have a long history of no credit losses. Accordingly, no allowance for credit losses has been recorded for these securities.

Regarding securities issued by state and political subdivisions and other HTM securities, the adequacy of the reserve for credit loss is determined quarterly based on methodology similar to the methodology for determining the allowance for credit losses on loans. The methodology considers, but is not limited to: (i) issuer bond ratings, (ii) issuer geography, (iii) whether issuers continue to make timely principal and interest payments under the contractual terms of the securities, (iv) probability-weighted multiple scenario forecasts, and (v) the issuers’ size.

As a result of the balance sheet repositioning, the Company did not hold any investment securities classified as HTM as of March 31, 2026. Activity in the allowance for credit losses by investment security type for the three months ended March 31, 2025 on the Company’s HTM securities portfolio was as follows:


(In thousands)	State and Political Subdivisions		Other Securities		Total
Three Months Ended March 31, 2025
Held-to-maturity
Beginning balance, January 1, 2025	$	196	$	3,018	$	3,214
Provision for credit loss expense	—		—		—
Net (decrease) increase in allowance on previously impaired securities	(25)		25		—
Ending balance, March 31, 2025	$	171	$	3,043	$	3,214

Based upon the Company’s analysis of the underlying risk characteristics of its AFS portfolio, including credit ratings and other qualitative factors, as previously discussed, there was no provision for credit losses related to the Company’s AFS portfolio recorded for the three month periods ended March 31, 2026 or 2025.


	Three Months Ended March 31,
(In thousands)		2026		2025
Taxable:
Held-to-maturity		$	—	$	10,399
Available-for-sale		26,311		21,185

Non-taxable:
Held-to-maturity		—		10,051
Available-for-sale		5,571		5,622
Total		$	31,882	$	47,257

The amortized cost and estimated fair value by maturity of AFS securities as of March 31, 2026 are shown in the following table. Securities are classified according to their contractual maturities without consideration of principal amortization, potential prepayments or call options. Accordingly, actual maturities may differ from contractual maturities.


	Available-for-Sale
(In thousands)		Amortized Cost		Fair Value
One year or less		$	9,044	$	8,945
After one through five years		99,070		98,511
After five through ten years		105,605		99,700
After ten years		1,016,912		816,200
Securities not due on a single maturity date		2,317,158		2,128,732
Other securities (no maturity)		198		198
Total		$	3,547,987	$	3,152,286

The carrying value, which approximates the fair value, of securities pledged as collateral, to secure public deposits and for other purposes, amounted to $1.85 billion at March 31, 2026 and $2.04 billion at December 31, 2025.

There were no gross realized gains and no gross realized losses from the call or sale of securities during the three months ended March 31, 2026 and 2025, as they were recognized at book value of the security.

The Company has entered into various hedging transactions to mitigate the impact of changing interest rates on the fair value of AFS securities. See Note 22, Derivative Instruments, for disclosure of the gains and losses recognized on derivative instruments and the cumulative fair value hedging adjustments to the carrying amount of the hedged securities.