Pension and Postretirement Benefit Plans - Future Benefit Payments (Details) - Funded $ in Millions	Dec. 31, 2019 USD ($)
Qualified and Non-qualified Pension Benefits \| United States
Future Pension and Postretirement Benefit Payments
2020 Benefit Payments	$ 1,103
2021 Benefit Payments	1,096
2022 Benefit Payments	1,104
2023 Benefit Payments	1,106
2024 Benefit Payments	1,111
Next five years	5,521
Qualified and Non-qualified Pension Benefits \| International
Future Pension and Postretirement Benefit Payments
2020 Benefit Payments	246
2021 Benefit Payments	253
2022 Benefit Payments	272
2023 Benefit Payments	284
2024 Benefit Payments	302
Next five years	1,656
Postretirement Benefits
Future Pension and Postretirement Benefit Payments
2020 Benefit Payments	121
2021 Benefit Payments	128
2022 Benefit Payments	136
2023 Benefit Payments	142
2024 Benefit Payments	148
Next five years	$ 789

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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 benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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

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