Pension Plans, Retirement Benefits and Savings Plans (Details) - Future Payments $ in Millions	Dec. 31, 2019 USD ($)
Pension Plans [Member]
Estimated Future Benefit Payments
Benefits expected to be paid, 2020	$ 250
Benefits expected to be paid, 2021	261
Benefits expected to be paid, 2022	265
Benefits expected to be paid, 2023	273
Benefits expected to be paid, 2024	276
Benefits expected to be paid, 2025 through 2029	1,400
Postretirement Benefit Plans [Member]
Estimated Future Benefit Payments
Benefits expected to be paid, 2020	12
Benefits expected to be paid, 2021	12
Benefits expected to be paid, 2022	12
Benefits expected to be paid, 2023	12
Benefits expected to be paid, 2024	12
Benefits expected to be paid, 2025 through 2029	$ 55

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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=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 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.

+ References

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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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