v3.25.1
Employee Benefit Plans (Tables)
 3 Months Ended
Mar. 31, 2025
Retirement Benefits [Abstract]  
Schedule of Net Benefit Costs
The following table provides the components of the net periodic benefit cost for the defined benefit pension and OPEB plans.
Three Months Ended March 31
 Pension Benefits  
 U.S. PlansU.K. PlanOPEB
 202520242025202420252024
(in millions of dollars)
Service Cost$2.4 $2.3 $— $— $— $— 
Interest Cost21.4 20.7 2.1 1.9 1.0 1.0 
Expected Return on Plan Assets(21.8)(22.8)(2.2)(2.1)(0.1)(0.1)
Amortization of:
   Net Actuarial Loss (Gain)
3.7 3.7 0.7 0.7 (0.3)(0.2)
   Prior Service Credit— — — — (0.1)(0.1)
Total Net Periodic Benefit Cost
$5.7 $3.9 $0.6 $0.5 $0.5 $0.6