v3.25.2
Components of Net Periodic Benefit Cost
 6 Months Ended
Jun. 30, 2025
Retirement Benefits [Abstract]  
Components of Net Periodic Benefit Cost Components of Net Periodic Benefit Cost
    Pension Plan, Retirement Income Maintenance Plan (the "RIM Plan") Post-retirement Plan, and Split-Dollar Life Insurance Plans

    The Company maintains a single employer, tax-qualified defined benefit pension plan (the "Pension Plan") which covers full-time employees that satisfy the Pension Plan's eligibility requirements. The benefits are based on years of service and the employee's average compensation for the highest five consecutive years of employment. Effective October 1, 2018, newly hired employees are not eligible to participate in the Bank's Pension Plan as the Plan was closed to new employees as of that date.

    The Company also maintains a Retirement Income Maintenance Plan (the "RIM Plan") which is a non-qualified defined benefit plan which provides benefits to all employees of the Company if their benefits under the Pension Plan are limited by Internal Revenue Code Sections 415 and 401(a)(17).    

In addition, the Company provides certain health care and life insurance benefits to eligible retired employees under a Post-retirement Plan. The Company accrues the cost of retiree health care and other benefits during the employee's period of active service. Effective January 1, 2019, the Post-retirement Plan was closed to new hires.

The Company also provides life insurance benefits to eligible employees under an endorsement split-dollar life insurance program. The Company recognizes a liability for future benefits applicable to endorsement split-dollar life insurance arrangements that provide death benefits post-retirement. Through its mergers, the Company recognized additional liability for future benefits applicable to endorsement split-dollar life insurance arrangements that provide death benefits post-retirement under the programs of certain other previously acquired banks.

Net periodic (income) benefit cost for the Pension Plan, RIM Plan, Post-retirement Plan and Split-Dollar Life Insurance plan benefits for the three and six months ended June 30, 2025 and 2024, includes the following components:

 For the Three Months Ended June 30,
Pension PlanRIM PlanPost-retirement PlanSplit-Dollar Life Insurance
20252024202520242025202420252024 Affected Line Item in the Consolidated Statements of Income
(In thousands)
Service cost$1,017 $1,212 $52 $61 $51 $54 $57 $57 Compensation and employee benefits
Interest cost3,294 3,100 169 162 287 248 216 208 Other non-interest expense
Expected return on plan assets(8,607)(8,119)— — — — — — Other non-interest expense
Amortization:
Prior service cost— — — — — — 13 14 Other non-interest expense
Net loss— 512 — 28 — — (22)— Other non-interest expense
Net periodic (income) benefit cost$(4,296)$(3,295)$221 $251 $338 $302 $264 $279 
13.    Components of Net Periodic Benefit Cost (continued)

For the Six Months Ended June 30,
Pension PlanRIM PlanPost-retirement PlanSplit-Dollar Life Insurance
20252024202520242025202420252024Affected Line Item in the Consolidated Statements of Income
(In thousands)
Service cost$2,034 $2,424 $104 $122 $102 $108 $114 $114 Compensation and employee benefits
Interest cost6,587 6,200 338 324 574 496 432 416 Other non-interest expense
Expected return on plan assets(17,214)(16,239)— — — — — — Other non-interest expense
Amortization:
Prior service cost— — — — — — 26 28 Other non-interest expense
Net loss— 1,024 — 56 — — (44)— Other non-interest expense
Net periodic (income) benefit cost$(8,593)$(6,591)$442 $502 $676 $604 $528 $558 
For the three and six months ended June 30, 2025 and 2024, no contribution was made to the Pension Plan. The net periodic (income) cost for pension benefits, other post-retirement and split-dollar life insurance benefits for the three and six months ended June 30, 2025 was calculated using the most recent available benefit valuations.