Pension and Other Postretirement Benefit Plans - Benefit Payments (Details) - United States [Member] $ in Millions	Dec. 31, 2018 USD ($)
Pension Benefits [Member]
Benefit payments including expected future services [Abstract]
Paid in 2019	$ 324
Paid in 2020	311
Paid in 2021	313
Paid in 2022	316
Paid in 2023	318
Paid in 2024-2028	1,549
Other Postretirement Benefits [Member]
Benefit payments including expected future services [Abstract]
Paid in 2019	25
Paid in 2020	23
Paid in 2021	22
Paid in 2022	20
Paid in 2023	19
Paid in 2024-2028	$ 72

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- Definition

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=108410482&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.

+ References

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

+ References

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

+ References

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

+ References

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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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