v3.20.2

Pension and Other Postretirement Benefits - Expenses (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Pension benefits |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Net periodic benefit cost | $ 73 | $ 2 | $ 94 | $ 3
Multiemployer contribution | 0 | 14 | 0 | 30
Cost allocation | 0 | (5) | (1) | (10)
Pension and other postretirement benefits cost | 18 | 21 | 38 | 43
Pension benefits | Cumulative Direct Plan |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Net periodic benefit cost | 18 | 2 | 39 | 3
Other postretirement benefits |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Net periodic benefit cost | 6 | 0 | 12 | 0
Multiemployer contribution | 0 | 6 | 0 | 11
Cost allocation | 0 | (1) | 0 | (2)
Pension and other postretirement benefits cost | 6 | 7 | 12 | 13
Other postretirement benefits | Cumulative Direct Plan |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Net periodic benefit cost | $ 6 | $ 0 | $ 12 | $ 0

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