XML 32 R74.htm IDEA: XBRL DOCUMENT v3.20.1
Pension And Other Postretirement Benefits (Components Of The Plans' Net Periodic Benefits Cost) (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Pension Plan    
Defined Benefit Plan Disclosure [Line Items]    
Service Cost [1] $ 8.0 $ 7.3
Interest cost [1] 13.5 18.2
Expected return on assets [1] (28.4) (27.2)
Amortization of prior service credit [1] 0.2 0.0
Recognized actuarial loss [1] 8.7 11.4
Total Net Periodic Benefits Cost 2.0 9.7
Other Postretirement Benefit Plan    
Defined Benefit Plan Disclosure [Line Items]    
Service Cost [1] 1.6 1.3
Interest cost [1] 3.9 4.8
Expected return on assets [1] (3.6) (3.3)
Amortization of prior service credit [1] (0.5) (0.8)
Recognized actuarial loss [1] 1.3 0.5
Total Net Periodic Benefits Cost $ 2.7 $ 2.5
[1] The service cost component and all non-service cost components of net periodic benefit cost are presented in "Operation and maintenance" and "Other, net", respectively, on the Condensed Statements of Consolidated Income (unaudited).