v3.25.2
PENSION PLANS AND RETIREMENT BENEFITS (Tables)
 6 Months Ended
Jun. 30, 2025
Retirement Benefits [Abstract]  
Components of Net Periodic Benefit (Income) Cost
Pension BenefitsOther Postretirement Benefits
 Three Months Ended June 30,Three Months Ended June 30,
2025202420252024
Components of Net Periodic Benefit (Income) Cost($ in millions)
Service cost$1.2 $1.2 $0.2 $0.2 
Interest cost24.9 25.5 0.4 0.5 
Expected return on plans’ assets(31.7)(33.8)— — 
Amortization of prior service cost(0.1)(0.2)(0.1)— 
Recognized actuarial loss1.6 1.8 0.1 0.3 
Net periodic benefit (income) cost$(4.1)$(5.5)$0.6 $1.0 
Pension BenefitsOther Postretirement Benefits
 Six Months Ended June 30,Six Months Ended June 30,
2025202420252024
Components of Net Periodic Benefit (Income) Cost($ in millions)
Service cost$2.2 $2.5 $0.3 $0.4 
Interest cost49.4 50.6 0.7 0.9 
Expected return on plans’ assets(63.4)(67.7)— — 
Amortization of prior service cost(0.3)(0.3)(0.2)— 
Recognized actuarial loss3.0 3.3 0.2 0.5 
Net periodic benefit (income) cost$(9.1)$(11.6)$1.0 $1.8