v3.20.2
Pension and Other Postretirement Benefits - Net Periodic Benefit Cost (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Pension benefits        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Service cost $ 6 $ 1 $ 16 $ 2
Interest cost 27 1 81 3
Expected return on plan assets (42) (2) (127) (4)
Settlement 31 1 92 3
Amortization of prior service benefit 0 0 (1) 0
Net periodic benefit cost 25 1 119 4
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement 3 0 58 0
Other postretirement benefits        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Service cost 1 0 3 0
Interest cost 2 0 10 0
Settlement 3 0 6 0
Amortization of prior service benefit (1) 0 (2) 0
Net periodic benefit cost $ 5 $ 0 $ 17 $ 0