Annual report pursuant to Section 13 and 15(d)

Pension And Other Postretirement Benefit Programs - Healthcare Trend Rates (Details)

v3.20.1
Pension And Other Postretirement Benefit Programs - Healthcare Trend Rates (Details) - Retiree Health and Life Insurance Plans
$ in Millions
12 Months Ended
Dec. 31, 2019
USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]  
Effect on total service and interest cost components, one percentage point increase $ 0.0
Effect on total service and interest cost components, one percentage point decrease 0.0
Effect on postretirement benefit obligation, one percentage point increase (0.9)
Effect on postretirement benefit obligation, one percentage point decrease $ 1.2