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Pension and Other Postretirement Benefits - Narrative (Details) - USD ($) $ in Millions |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Mar. 11, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Restructuring and other charges |  | $ 5 |  | $ 105 | $ 14 | $ 144
Settlement charges |  | (3) |  | (64) | (6) | (64)
Increase (decrease) in minimum required pension funding | $ 120 |  |  |  |  |
Pension Settlement Cost |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Restructuring and other charges |  | 3 |  |  | 6 |
Pension benefits |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Settlement charges |  | $ (3) |  | (64) | $ (6) | $ (64)
Pension benefits | US |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Settlement charges |  |  |  | 2 |  |
Increase (decrease) in obligation, pension benefits |  |  |  | 6 |  |
Pension benefits | Foreign Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Settlement charges |  |  |  | $ 62 |  |
Other postretirement benefits |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Increase (decrease) in obligation, pension benefits |  |  | $ 39 |  |  |

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=123453770&loc=SL108413299-114919 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(7) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 + Details
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