v3.26.1
Investments (Tables)
 3 Months Ended
Mar. 31, 2026
Investments, Debt and Equity Securities [Abstract]  
Summary of Amortized Costs and Estimated Fair Values of Available-For-Sale Securities 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
March 31, 2026    
Obligations of states and political subdivisions$5,303 $1 $(50)$5,254 
MBS issued or guaranteed by U.S. government-sponsored enterprises
704,818 6,053 (44,361)666,510 
CMO issued or guaranteed by U.S. government-sponsored enterprises
219,617 695 (6,870)213,442 
Subordinated corporate bonds
16,730 118 (437)16,411 
Total AFS debt securities$946,468 $6,867 $(51,718)$901,617 
December 31, 2025    
Obligations of states and political subdivisions$5,303 $1 $(29)$5,275 
MBS issued or guaranteed by U.S. government-sponsored enterprises720,634 7,540 (43,785)684,389 
CMO issued or guaranteed by U.S. government-sponsored enterprises230,028 1,141 (6,796)224,373 
Subordinated corporate bonds
16,721 16 (373)16,364 
Total AFS debt securities$972,686 $8,698 $(50,983)$930,401 
The following table summarizes the Company’s other investments as presented on the consolidated statements of condition, as of the dates indicated:
(In thousands)March 31,
2026		December 31,
2025
FHLBB$14,649 $17,735 
FRB8,692 8,692 
Other
70 70 
Total other investments$23,411 $26,497 
Schedule of Realized Gain (Loss)
The following table details the Company’s sales of AFS debt securities for the periods indicated below:
Three Months Ended
March 31,
(In thousands)20262025
Proceeds from sales(1)
$— $56,432 
Gross realized gains
— — 
Gross realized losses— — 
(1)     Shortly after closing the Northway acquisition, the Company sold certain acquired AFS debt securities at fair value, and, therefore, no gain or loss was recognized on the sale.
The following table presents the Company’s AFS debt securities with gross unrealized losses, for which an ACL has not been recorded, segregated by the length of time the securities have been in a continuous loss position, as of the dates indicated:
 Less Than 12 Months12 Months or MoreTotal
(In thousands, except number of holdings)Number of
Holdings		Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses
March 31, 2026     
Obligations of states and political subdivisions7 $3,287 $(37)$386 $(13)$3,673 $(50)
MBS issued or guaranteed by U.S. government-sponsored enterprises149 77,294 (686)329,675 (43,675)406,969 (44,361)
CMO issued or guaranteed by U.S. government-sponsored enterprises57 54,376 (534)63,093 (6,336)117,469 (6,870)
Subordinated corporate bonds
7 948 (52)12,114 (385)13,062 (437)
Total AFS debt securities220 $135,905 $(1,309)$405,268 $(50,409)$541,173 $(51,718)
December 31, 2025      
Obligations of states and political subdivisions7 $547 $(3)$3,147 $(26)$3,694 $(29)
MBS issued or guaranteed by U.S. government-sponsored enterprises152 79,930 (379)332,788 (43,406)412,718 (43,785)
CMO issued or guaranteed by U.S. government-sponsored enterprises55 46,678 (332)66,255 (6,464)112,933 (6,796)
Subordinated corporate bonds
6 — — 12,129 (373)12,129 (373)
Total AFS debt securities220 $127,155 $(714)$414,319 $(50,269)$541,474 $(50,983)
Contractual Obligation, Fiscal Year Maturity
The amortized cost and estimated fair values of the Company’s AFS debt securities by contractual maturity as of March 31, 2026, are shown below. 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$1,498 $1,478 
Due after one year through five years14,305 14,024 
Due after five years through ten years6,230 6,163 
Due after ten years— — 
Subtotal22,033 21,665 
Mortgage-related securities924,435 879,952 
Total$946,468 $901,617 
Debt Securities, Held-to-maturity The following table summarizes the amortized cost, estimated fair value and unrealized gains (losses) of HTM debt securities as of the dates indicated:
(In thousands)
Amortized
Cost(1)
Unrealized
Gains		Unrealized
Losses		Fair
Value
March 31, 2026
Obligations of U.S. government-sponsored enterprises$7,899 $— $(345)$7,554 
Obligations of states and political subdivisions55,519 45 (1,591)53,973 
MBS issued or guaranteed by U.S. government-sponsored enterprises262,774 — (17,358)245,416 
CMO issued or guaranteed by U.S. government-sponsored enterprises125,549 52 (10,448)115,153 
Subordinated corporate bonds
21,516 928 (136)22,308 
Total HTM debt securities $473,257 $1,025 $(29,878)$444,404 
December 31, 2025
Obligations of U.S. government-sponsored enterprises$7,865 $— $(278)$7,587 
Obligations of states and political subdivisions55,802 167 (1,077)54,892 
MBS issued or guaranteed by U.S. government-sponsored enterprises271,168 — (16,933)254,235 
CMO issued or guaranteed by U.S. government-sponsored enterprises128,966 84 (10,391)118,659 
Subordinated corporate bonds
21,491 1,120 (163)22,448 
Total HTM debt securities$485,292 $1,371 $(28,842)$457,821 
(1)Amortized cost presented above includes unamortized unrealized losses from the aforementioned transfer from AFS to HTM securities that occurred in 2022. As of March 31, 2026 and December 31, 2025, the unamortized, unrealized losses on the 2022 transfer included within amortized cost were as follows: (1) $686,000 and $720,000 in obligations of U.S. government-sponsored enterprises, (2) $4.5 million and $4.6 million in obligations of state and political subdivisions, (3) $25.9 million and $26.8 million in MBS, (4) $13.9 million and $14.4 million in CMO, and (5) $16,000 and $23,000 in subordinated corporate bonds, respectively.
Amortized Cost and Estimated Fair Values of Debt Securities by Contractual Maturity The amortized cost and estimated fair values of HTM debt securities by contractual maturity as of March 31, 2026 are shown below. 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$1,018 $1,029 
Due after one year through five years9,755 9,504 
Due after five years through ten years35,093 35,528 
Due after ten years39,068 37,774 
Subtotal84,934 83,835 
Mortgage-related securities388,323 360,569 
Total$473,257 $444,404