Retirement Plans and Other Retiree Benefits - Expected Contributions and Benefit Payments (Details) $ in Millions	Dec. 31, 2020 USD ($)
Total benefit payments [Abstract]
2021	$ 245
2022	246
2023	249
2024	253
2025	252
2026-2030	1,254
Other Retiree Benefit Plans
Total benefit payments [Abstract]
2021	49
2022	49
2023	50
2024	51
2025	52
2026-2030	269
United States \| Pension Plans
Total benefit payments [Abstract]
2021	154
2022	156
2023	157
2024	156
2025	155
2026-2030	741
International \| Pension Plans
Total benefit payments [Abstract]
2021	42
2022	41
2023	42
2024	46
2025	45
2026-2030	$ 244

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- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ 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 (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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