XML 71 R61.htm IDEA: XBRL DOCUMENT v3.10.0.1
Schedule of Employee Benefit Plans Components of Net Periodic Benefit Cost (Credit) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement $ 0.0 $ 2.9 $ 0.0 $ 2.9
Pension Plan [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Service cost 1.1 0.7 3.2 2.6
Interest cost 6.9 7.2 20.6 21.4
Expected asset return (11.4) (11.1) (34.4) (32.7)
Amortized loss 2.2 1.9 6.6 5.4
Amortized prior service credit 0.0 (0.1) 0.1 (0.1)
Curtailment 0.0 0.0 3.2 0.0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement 0.0 2.9 0.0 2.9
Net periodic benefit cost (credit) (1.2) 1.5 (0.7) (0.5)
Other Postretirement Benefits Plan [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Service cost 0.1 0.1 0.3 0.3
Interest cost 3.1 3.3 9.3 9.9
Amortized loss 0.2 0.2 0.6 0.5
Amortized prior service credit (0.7) (0.8) (2.0) (2.1)
Net periodic benefit cost 2.7 $ 2.8 8.2 $ 8.6
Supplemental Executive Retirement Plan (SERP) [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment     11.6  
Other Operating Income (Expense) [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Components of net periodic benefit cost other than service cost $ 0.3   $ 0.8