Investment Securities

9 Months Ended

Sep. 30, 2025

Investments, Debt and Equity Securities [Abstract]

The following table summarizes the amortized cost and fair value of securities that are classified as available-for-sale and held-to-maturity:


	September 30, 2025
	Available-for-Sale
	Amortized Cost		Allowance for Credit Losses		Net Carrying Amount		Gross Unrealized Gains		Gross Unrealized (Losses)		Estimated Fair Value
	(In thousands)
U.S. government-sponsored enterprises	$	254,741	$	—	$	254,741	$	968	$	(8,394)	$	247,315
U.S. government-sponsored mortgage-backed securities	1,378,237		—		1,378,237		1,360		(138,541)		1,241,056
Private mortgage-backed securities	155,155		—		155,155		163		(7,417)		147,901
Non-government-sponsored asset backed securities	171,752		—		171,752		348		(1,067)		171,033
State and political subdivisions	959,533		—		959,533		1,015		(78,219)		882,329
Other securities	244,462		—		244,462		1,768		(11,368)		234,862
Total	$	3,163,880	$	—	$	3,163,880	$	5,622	$	(245,006)	$	2,924,496


	September 30, 2025
	Held-to-Maturity
	Amortized Cost		Allowance for Credit Losses		Net Carrying Amount		Gross Unrealized Gains		Gross Unrealized (Losses)		Estimated Fair Value
	(In thousands)
U.S. government-sponsored enterprises	$	43,770	$	—	$	43,770	$	—	$	(1,523)	$	42,247
U.S. government-sponsored mortgage-backed securities	118,662		—		118,662		349		(3,366)		115,645
State and political subdivisions	1,103,773		(2,005)		1,101,768		95		(102,636)		999,227

Total	$	1,266,205	$	(2,005)	$	1,264,200	$	444	$	(107,525)	$	1,157,119


	December 31, 2024
	Available-for-Sale
	Amortized Cost		Allowance for Credit Losses		Net Carrying Amount		Gross Unrealized Gains		Gross Unrealized (Losses)		Estimated Fair Value
	(In thousands)
U.S. government-sponsored enterprises	$	297,698	$	—	$	297,698	$	1,164	$	(14,072)	$	284,790
U.S. government-sponsored mortgage-backed securities	1,527,463		—		1,527,463		760		(203,539)		1,324,684
Private mortgage-backed securities	184,643		—		184,643		—		(13,249)		171,394
Non-government-sponsored asset backed securities	228,751				228,751		331		(3,434)		225,648
State and political subdivisions	956,055		—		956,055		335		(86,029)		870,361
Other securities	215,662		(2,195)		213,467		576		(18,281)		195,762
Total	$	3,410,272	$	(2,195)	$	3,408,077	$	3,166	$	(338,604)	$	3,072,639


	December 31, 2024
	Held-to-Maturity
	Amortized Cost		Allowance for Credit Losses		Net Carrying Amount		Gross Unrealized Gains		Gross Unrealized (Losses)		Estimated Fair Value
	(In thousands)
U.S. government-sponsored enterprises	$	43,560	$	—	$	43,560	$	—	$	(3,021)	$	40,539
U.S. government-sponsored mortgage-backed securities	124,169		—		124,169		—		(6,695)		117,474
State and political subdivisions	1,109,480		(2,005)		1,107,475		39		(122,587)		984,927

Total	$	1,277,209	$	(2,005)	$	1,275,204	$	39	$	(132,303)	$	1,142,940

Assets, principally investment securities, having a carrying value of approximately $2.66 billion and $2.61 billion at September 30, 2025 and December 31, 2024, respectively, were pledged to secure public deposits, as collateral for repurchase agreements, and for other purposes required or permitted by law. Investment securities pledged as collateral for repurchase agreements totaled approximately $146.0 million and $162.4 million at September 30, 2025 and December 31, 2024, respectively.

The amortized cost and estimated fair value of securities classified as available-for-sale and held-to-maturity at September 30, 2025, by contractual maturity, are shown below. Expected maturities could differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity date are shown separately.


	Available-for-Sale				Held-to-Maturity
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
	(In thousands)
Due in one year or less	$	32,853	$	32,425	$	—	$	—
Due after one year through five years	257,956		247,955		104,620		101,940
Due after five years through ten years	394,695		375,621		364,055		338,975
Due after ten years	773,232		708,505		678,868		600,559
U.S. government-sponsored mortgage-backed securities	1,378,237		1,241,056		118,662		115,645
Private mortgage-backed securities	155,155		147,901		—		—
Non-government-sponsored asset backed securities	171,752		171,033		—		—
Total	$	3,163,880	$	2,924,496	$	1,266,205	$	1,157,119

During the three and nine months ended September 30, 2025 and 2024, no available-for-sale securities were sold.

The following table shows gross unrealized losses and estimated fair value of investment securities classified as available-for-sale and held-to-maturity, aggregated by investment category and length of time that individual investment securities have been in a continuous loss position as of September 30, 2025 and December 31, 2024.


	September 30, 2025
	Less Than 12 Months				12 Months or More				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
	(In thousands)
Available-for-sale:
U.S. government-sponsored enterprises	$	16,429	$	(64)	$	164,831	$	(8,330)	$	181,260	$	(8,394)
U.S. government-sponsored mortgage-backed securities	15,657		(22)		1,128,946		(138,519)		1,144,603		(138,541)
Private mortgage-backed securities	—		—		138,047		(7,417)		138,047		(7,417)
Non-government-sponsored asset backed securities	642		(1)		56,007		(1,066)		56,649		(1,067)
State and political subdivisions	28,597		(911)		750,624		(77,308)		779,221		(78,219)
Other securities	11,349		(78)		166,792		(11,290)		178,141		(11,368)
Total	$	72,674	$	(1,076)	$	2,405,247	$	(243,930)	$	2,477,921	$	(245,006)
Held-to-maturity:
U.S. government-sponsored enterprises	$	—	$	—	$	42,247	$	(1,523)	$	42,247	$	(1,523)
U.S. government-sponsored mortgage-backed securities	6,583		(42)		74,627		(3,324)		81,210		(3,366)


State and political subdivisions	12,467		(482)		982,504		(102,154)		994,971		(102,636)
Total	$	19,050	$	(524)	$	1,099,378	$	(107,001)	$	1,118,428	$	(107,525)


	December 31, 2024
	Less Than 12 Months				12 Months or More				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
	(In thousands)
Available-for-sale:
U.S. government-sponsored enterprises	$	25,946	$	(326)	$	161,759	$	(13,746)	$	187,705	$	(14,072)
U.S. government-sponsored mortgage-backed securities	34,597		(1,088)		1,215,317		(202,451)		1,249,914		(203,539)
Private mortgage-backed securities	9,491		(129)		161,903		(13,120)		171,394		(13,249)
Non-government-sponsored asset backed securities	10,849		(60)		92,857		(3,374)		103,706		(3,434)
State and political subdivisions	46,591		(1,230)		761,289		(84,799)		807,880		(86,029)
Other securities	7,157		(911)		173,204		(17,370)		180,361		(18,281)
Total	$	134,631	$	(3,744)	$	2,566,329	$	(334,860)	$	2,700,960	$	(338,604)
Held-to-maturity:
U.S. government-sponsored enterprises	$	—	$	—	$	40,539	$	(3,021)	$	40,539	$	(3,021)
U.S. government-sponsored mortgage-backed securities	48,254		(1,979)		69,220		(4,716)		117,474		(6,695)


State and political subdivisions	29,612		(1,037)		954,335		(121,550)		983,947		(122,587)
Total	$	77,866	$	(3,016)	$	1,064,094	$	(129,287)	$	1,141,960	$	(132,303)

Debt securities available-for-sale ("AFS") are reported at fair value with unrealized holding gains and losses reported as a separate component of stockholders’ equity and other comprehensive income (loss), net of taxes. Securities that are held as available-for-sale are used as a part of our asset/liability management strategy. Securities that may be sold in response to interest rate changes, changes in prepayment risk, the need to increase regulatory capital, and other similar factors are classified as available-for-sale. The Company evaluates all securities quarterly to determine if any securities in a loss position require a provision for credit losses. The Company first assesses whether it intends to sell or is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through income. For securities that do not meet these criteria, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers the extent to which fair value is less than amortized cost, changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded for the credit loss, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that has not been recorded through an allowance for credit losses is recognized in other comprehensive income. The Company has made the election to exclude accrued interest receivable on AFS securities from the estimate of credit losses and report accrued interest separately on the consolidated balance sheets. Changes in the allowance for credit losses are recorded as provision for (or reversal of) credit loss expense. Losses are charged against the allowance when management believes the uncollectability of a security is confirmed or when either of the criteria regarding intent or requirement to sell is met.

Debt securities held-to-maturity ("HTM"), which include any security for which we have the positive intent and ability to hold until maturity, are reported at historical cost adjusted for amortization of premiums and accretion of discounts. Premiums and discounts are amortized/accreted to the call date to interest income using the constant effective yield method over the estimated life of the security. The Company evaluates all securities quarterly to determine if any securities in a loss position require a provision for credit losses. The Company measures expected credit losses on HTM securities on a collective basis by major security type, with each type sharing similar risk characteristics. The estimate of expected credit losses considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. The Company has made the election to exclude accrued interest receivable on HTM securities from the estimate of credit losses and report accrued interest separately on the consolidated balance sheets. Changes in the allowance for credit losses are recorded as provision for (or reversal of) credit loss expense. Losses are charged against the allowance when management believes the uncollectability of a security is confirmed.

During the three and nine months ended September 30, 2025, the Company reversed the $2.2 million allowance for credit losses on the available-for-sale portfolio due to an upgrade in the credit quality of the subordinated debt investment securities for which an allowance had been recorded. However, the Company determined the $2.0 million allowance for credit losses on the held-to-maturity portfolio was adequate. Therefore, no additional provision was considered necessary.


Available-for-Sale Investment Securities
	September 30, 2025		December 31, 2024
Allowance for credit losses:	(In thousands)
Beginning balance, January 1	$	2,195	$	2,525
Recovery of credit losses	(2,195)		(330)
Balance, September 30	$	—	$	2,195
Recovery of credit loss			—
Balance, December 31, 2024			$	2,195


Held-to-Maturity Investment Securities
	September 30, 2025		December 31, 2024
Allowance for credit losses:	(In thousands)
Beginning balance, January 1	$	2,005	$	2,005
Provision for credit losses	—		—
Balance, September 30	$	2,005	$	2,005
Provision for credit loss			—
Balance, December 31, 2024			$	2,005

For the nine months ended September 30, 2025, the Company had available-for-sale investment securities with approximately $245.0 million in unrealized losses, of which $243.9 million had been in continuous loss positions for more than twelve months. The Company’s assessments indicated the cause of the market depreciation was primarily due to the change in interest rates and not the issuer’s financial condition or downgrades by rating agencies. In addition, approximately 43.5% of the principal balance from the Company’s investment portfolio will mature or are expected to pay down within five years or less. As a result, the Company has the ability and intent to hold such securities until maturity.

As of September 30, 2025, the Company's available-for-sale securities portfolio consisted of 1,494 investment securities, 1,206 of which were in an unrealized loss position. As noted in the table above, the total amount of the unrealized loss was $245.0 million. The U.S. government-sponsored enterprises portfolio contained unrealized losses of $8.4 million on 61 securities. The U.S. government-sponsored mortgage-backed securities portfolio contained $138.5 million of unrealized losses on 616 securities, and the private mortgage-backed securities portfolio contained $7.4 million of unrealized losses on 29 securities. The non-government-sponsored asset backed securities portfolio contained $1.1 million of unrealized losses on 15 securities. The state and political subdivisions portfolio contained $78.2 million of unrealized losses on 426 securities. In addition, the other securities portfolio contained $11.4 million of unrealized losses on 59 securities. The unrealized losses on the Company's investments were primarily a result of interest rate changes, and the Company expects to recover the amortized cost basis over the term of the securities. The Company has determined that, as of September 30, 2025, a reserve for credit losses is not necessary because the decline in market value was attributable to changes in interest rates and not credit quality, and because the Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost basis, which may be maturity.

As of September 30, 2025, the Company's held-to-maturity securities portfolio consisted of 514 investment securities, 494 of which were in an unrealized loss position. As noted in the table above, the total amount of the unrealized loss was $107.5 million. The U.S. government-sponsored enterprises portfolio contained unrealized losses of $1.5 million on 5 securities. The U.S. government-sponsored mortgage-backed securities portfolio contained unrealized losses of $3.4 million on 14 securities. The state and political subdivisions portfolio contained $102.6 million of unrealized losses on 475 securities. The unrealized losses on the Company's investments were a result of interest rate changes. The Company expects to recover the amortized cost basis over the term of the securities. Because the decline in market value was attributable to changes in interest rates and not credit quality, the Company has determined that an additional provision for credit losses was not necessary as of September 30, 2025.

The following table summarizes bond ratings for the Company’s held-to-maturity portfolio, based upon amortized cost, issued by state and political subdivisions and other securities as of September 30, 2025:


	State and political subdivisions		U.S. government-sponsored enterprises		U.S. government-sponsored mortgage-backed securities		Total
	(In thousands)
Aaa/AAA	$	233,372	$	43,770	$	—	$	277,142
Aa/AA	832,351		—		—		832,351
A	32,589		—		—		32,589

Not rated	5,461		—		—		5,461
Agency Backed	—		—		118,662		118,662
Total	$	1,103,773	$	43,770	$	118,662	$	1,266,205

Income earned on securities for the three and nine months ended September 30, 2025 and 2024, is as follows:


	Three Months Ended September 30,				For the Nine Months Ended September 30,
	2025		2024		2025		2024
	(In thousands)
Taxable
Available-for-sale	$	18,899	$	23,550	$	57,991	$	74,439
Held-to-maturity	7,427		7,456		22,212		22,383
Non-taxable
Available-for-sale	4,706		4,612		13,865		13,971
Held-to-maturity	3,037		3,092		9,154		9,305
Total	$	34,069	$	38,710	$	103,222	$	120,098