XML 31 R18.htm IDEA: XBRL DOCUMENT v3.21.2
Components of Net Periodic Benefit Cost
 9 Months Ended
Sep. 30, 2021
Retirement Benefits [Abstract]  
Components of Net Periodic Benefit Cost Components of Net Periodic Benefit Cost
Pension Benefits
Three months ended September 30,
Nine months ended September 30,
2021
2020
2021
2020
Service cost$1.2 $1.3 $3.5 $3.7 
Interest cost2.4 2.9 7.3 8.5 
Expected return on plan assets(5.6)(5.3)(16.8)(15.6)
Amortization of prior service costs0.0 0.10.1 0.1 
Amortization of net loss1.5 1.6 4.5 4.9 
Net periodic benefit cost$(0.5)$0.6 $(1.4)$1.6 
Other Postretirement Benefits
Three months ended September 30,
Nine months ended September 30,
2021
2020
2021
2020
Service cost$0.1 $0.0 $0.2 $0.2 
Interest cost0.6 0.8 1.8 2.3 
Amortization of prior service cost(0.8)(0.8)(2.4)(2.4)
Amortization of net loss0.6 0.5 1.7 1.6 
Net periodic benefit cost$0.5 $0.5 $1.3 $1.7