Pension and Other Postretirement Plans - Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2020 USD ($)
Pension Benefits
Pension and Other Postretirement
2021	$ 325
2022	339
2023	353
2024	351
2025	376
Years 2026 – 2030	2,113
Other Postretirement Benefits
Pension and Other Postretirement
2021	88
2022	118
2023	100
2024	87
2025	83
Years 2026 – 2030	$ 359

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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

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

+ References

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- Definition

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

+ References

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

+ References

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

+ References

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

+ References

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