v3.20.1

Pension and Other Postretirement Benefits - Expenses (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Net periodic benefit cost | $ 26 |
Multiemployer contribution |  | $ 28
Pension benefits |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Net periodic benefit cost | 21 | 1
Multiemployer contribution | 0 | 16
Cost allocation | (1) | 5
Pension and other postretirement benefits cost | 20 | 22
Other postretirement benefits |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Net periodic benefit cost | 6 | 0
Multiemployer contribution | 0 | 5
Cost allocation | 0 | 1
Pension and other postretirement benefits cost | $ 6 | $ 6

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- Definition Multiemployer Plan, Contribution Expenses + References No definition available. + Details
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- Definition Pension and Other Postretirement Benefits Cost, Allocated Costs + References No definition available. + Details
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of cost (reversal of cost) for pension and other postretirement benefits. + References No definition available. + Details
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