Pension and Postretirement Benefit Plans - Future Benefit Payments (Details) - Funded $ in Millions	Dec. 31, 2020 USD ($)
Qualified and Non-qualified Pension Benefits \| United States
Future Pension and Postretirement Benefit Payments
2021 Benefit Payments	$ 1,127
2022 Benefit Payments	1,134
2023 Benefit Payments	1,135
2024 Benefit Payments	1,134
2025 Benefit Payments	1,139
Next five years	5,619
Qualified and Non-qualified Pension Benefits \| International
Future Pension and Postretirement Benefit Payments
2021 Benefit Payments	263
2022 Benefit Payments	276
2023 Benefit Payments	292
2024 Benefit Payments	311
2025 Benefit Payments	319
Next five years	1,752
Postretirement Benefits
Future Pension and Postretirement Benefit Payments
2021 Benefit Payments	127
2022 Benefit Payments	133
2023 Benefit Payments	140
2024 Benefit Payments	145
2025 Benefit Payments	152
Next five years	$ 792

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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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- Definition

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.

+ References

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+ References

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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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