Trading securities are reported on the Company's consolidated statements of condition at fair value. As of December 31, 2023 and 2022, the fair value of the Company's trading securities were $4.6 million and $4.0 million, respectively. These securities are held in a rabbi trust account and invested in mutual funds. The trading securities will be used for future payments associated with the Company’s deferred compensation plan for eligible employees and directors.

AFS debt securities are reported on the Company's consolidated statements of condition at fair value. The following table summarizes the amortized cost, estimated fair value and unrealized gains (losses) of AFS debt securities as of the dates indicated:


(In thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
December 31, 2023

Obligations of states and political subdivisions	$	6,429	$	1	$	(44)	$	6,386
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises	525,439		630		(65,978)		460,091
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises	149,387		1,161		(9,537)		141,011
Subordinated corporate bonds	21,682		1		(3,363)		18,320
Total AFS debt securities	$	702,937	$	1,793	$	(78,922)	$	625,808
December 31, 2022

Obligations of states and political subdivisions	$	49,678	$	11	$	(463)	$	49,226
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises	598,845		131		(84,957)		514,019
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises	122,760		—		(13,413)		109,347
Subordinated corporate bonds	25,677		3		(2,397)		23,283
Total AFS debt securities	$	796,960	$	145	$	(101,230)	$	695,875

In June of 2022, the Company transferred securities with a fair value of $520.3 million from AFS to HTM. The unrealized losses on the AFS debt securities at the time of the transfer were $72.1 million, pre-tax, and were reported within AOCI. These unrealized losses are being amortized over the remaining life of the securities from AOCI into the HTM securities on the consolidated statements of income. At December 31, 2023 and 2022, the net unrealized losses on the transferred securities reported within AOCI were $46.9 million and $52.2 million, respectively, net of a deferred tax asset of $12.8 million and $14.3 million, respectively.

The net unrealized losses on AFS debt securities reported within AOCI (excluding the aforementioned securities transferred from AFS to HTM) at December 31, 2023 and December 31, 2022 were $60.5 million and $79.4 million, respectively, and were net of a deferred tax asset of $16.6 million and $21.7 million, respectively.


		Less Than 12 Months				12 Months or More				Total
(In thousands, except number of holdings)	Number of Holdings	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
December 31, 2023

Obligations of states and political subdivisions	6	$	2,345	$	(6)	$	1,437	$	(38)	$	3,782	$	(44)
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises	145	13,474		(23)		407,200		(65,955)		420,674		(65,978)
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises	43	19,620		(45)		62,869		(9,492)		82,489		(9,537)
Subordinated corporate bonds	11	—		—		17,319		(3,363)		17,319		(3,363)
Total AFS debt securities	205	$	35,439	$	(74)	$	488,825	$	(78,848)	$	524,264	$	(78,922)



December 31, 2022

Obligations of states and political subdivisions	83	$	42,276	$	(463)	$	—	$	—	$	42,276	$	(463)
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises	175	118,290		(11,521)		381,355		(73,436)		499,645		(84,957)
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises	64	47,340		(4,589)		62,007		(8,824)		109,347		(13,413)
Subordinated corporate bonds	13	7,687		(384)		14,593		(2,013)		22,280		(2,397)
Total AFS debt securities	335	$	215,593	$	(16,957)	$	457,955	$	(84,273)	$	673,548	$	(101,230)

As of December 31, 2023 and 2022, the unrealized losses on AFS debt securities have not been recognized into income because management does not intend to sell and it is not more-likely-than-not it will be required to sell any of the AFS debt securities before recovery of its amortized cost basis. Furthermore, the unrealized losses were due to changes in interest rates and other market conditions and were not reflective of credit events. Agency-backed and government-sponsored enterprise securities have a long history with no credit losses, including during times of severe stress. The principal and interest payments on agency-guaranteed debt is backed by the U.S. government. Government-sponsored enterprises similarly guarantee principal and interest payments and carry an implicit guarantee from the U.S. Department of the Treasury. Additionally, government-sponsored enterprise securities are exceptionally liquid, readily marketable, and provide a substantial amount of price transparency and price parity, indicating a perception of zero credit losses. Obligations of states and political subdivision are comprised solely of high credit quality (rated A- of higher) state and municipal obligations. High credit quality state and municipal obligations have a history of zero to near-zero credit loss. Subordinated corporate bonds are primarily comprised of investment grade senior notes and senior subordinated notes of other financial institutions.

At December 31, 2023 and 2022, total accrued interest receivable on AFS debt securities, which has been excluded from reported amortized cost basis on AFS debt securities, was $1.7 million and $1.9 million, respectively, and was reported within other assets on the consolidated statements of condition. An allowance was not carried on the accrued interest receivable at either date.

The amortized cost and estimated fair values of the Company’s AFS debt securities by contractual maturity are shown in the table below as of December 31, 2023. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Mortgage-related securities are shown in total, as their maturities are highly variable.


(In thousands)	Amortized Cost		Fair Value
Due in one year or less	$	1,000	$	1,000
Due after one year through five years	10,835		9,997
Due after five years through ten years	16,276		13,709
Due after ten years	—		—
Subtotal	28,111		24,706
Mortgage-related securities	674,826		601,102
Total	$	702,937	$	625,808


(In thousands)	Amortized Cost(1)		Unrealized Gains		Unrealized Losses		Fair Value
December 31, 2023
Obligations of U.S. government-sponsored enterprises	$	7,593	$	—	$	(528)	$	7,065
Obligations of states and political subdivisions	56,262		1,242		(731)		56,773
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises	304,850		—		(21,623)		283,227
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises	157,118		515		(13,497)		144,136
Subordinated corporate bonds	19,108		1,377		(1,091)		19,394
Total HTM debt securities	$	544,931	$	3,134	$	(37,470)	$	510,595
December 31, 2022
Obligations of U.S. government-sponsored enterprises	$	7,457	$	—	$	(777)	$	6,680
Obligations of states and political subdivisions	55,978		431		(1,610)		54,799
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises	317,406		—		(24,766)		292,640
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises	145,069		—		(13,724)		131,345
Subordinated corporate bonds	20,673		332		(276)		20,729
Total HTM debt securities	$	546,583	$	763	$	(41,153)	$	506,193

(1) Amortized cost presented above includes unamortized unrealized losses from the aforementioned transfer from AFS to HTM securities as of December 31, 2023 and 2022 as follows: (1) $992,000 and $1.1 million, respectively, in obligations of U.S. government-sponsored enterprises; (2) $5.6 million and $6.1 million, respectively, in obligations of state and political subdivisions; (3) $34.6 million and $38.4 million, respectively, in mortgage-backed securities; (4) $18.4 million and $20.7 million, respectively, in collateralized mortgage obligations; and (5) $85,000 and $117,000, respectively in subordinated corporate bonds.

For the year ended December 31, 2023, the Company recorded a provision for credit losses on its HTM debt securities portfolio of $1.8 million for the full write-off of a Signature Bank corporate bond due to Signature Bank’s failure in March 2023. The Company did not previously carry any ACL on the bond. In addition to the write-off of the Signature Bank corporate bond, the Company wrote-off accrued interest totaling $8,000 associated with the Signature Bank corporate bond and recorded a reversal of interest income on the consolidated statements of income for the year ended December 31, 2023. The Company did not record any provisions for credit losses on its HTM debt securities nor write-off any accrued interest for the years ended December 31, 2022 or 2021.

The following table presents the activity in the ACL on HTM debt securities, as reported under CECL, for the periods indicated:


	December 31,
(In thousands)	2023		2022
Beginning balance	$	—	$	—
HTM debt securities charged-off	(1,838)		—
Provision for HTM debt securities	1,838		—


Ending balance	$	—	$	—

As of December 31, 2023 and 2022, none of the Company's HTM debt securities were past due or on non-accrual status. The Company did not recognize any interest income on non-accrual HTM debt securities during the years ended December 31, 2023, 2022, and 2021. At December 31, 2023 and 2022, total accrued interest receivable on HTM debt securities was $1.7 million and no allowance was provided for. Accrued interest on HTM debt securities is reported within other assets on the consolidated statements of condition and excluded from reported amortized cost.

The amortized cost and estimated fair values of HTM debt securities by contractual maturity are shown in the table below as of December 31, 2023. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Mortgage-related securities are shown in total, as their


(In thousands)	Amortized Cost		Fair Value
Due in one year or less	$	502	$	498
Due after one year through five years	1,790		1,818
Due after five years through ten years	35,975		35,840
Due after ten years	44,696		45,076
Subtotal	82,963		83,232
Mortgage-related securities	461,968		427,363
Total	$	544,931	$	510,595

At December 31, 2023 and 2022, AFS and HTM debt securities with an amortized cost of $675.5 million and $821.9 million, respectively, and estimated fair values of $607.9 million and $726.5 million, respectively, were pledged to secure FHLBB advances, public deposits, and securities sold under agreements to repurchase, and for other purposes required or permitted by law.

The Company's FHLBB and FRB common stock are reported at cost within other investments on the consolidated statements of condition. The Company evaluates these investments for impairment based on the ultimate recoverability of the par value. The Company did not record any impairment on its FHLBB and FRB stock for the years ended December 31, 2023, 2022 and 2021.