Pension and Other Postretirement Benefits - Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2018 USD ($)
Pension
Portion of the benefit payments are expected to be paid
2019	$ 162
2020	165
2021	169
2022	172
2023	180
Years 2024-2028	895
Other Postretirement Benefits
Portion of the benefit payments are expected to be paid
2019	35
2020	36
2021	36
2022	37
2023	37
Years 2024-2028	$ 182

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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=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.

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

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

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Amount of benefits for defined benefit plan expected to be paid in third 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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