Pension and Other Postretirement Benefit Plans - Expected Benefit Payments and Future Contributions (Details) $ in Millions	Dec. 31, 2021 USD ($)
Pension Plans
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2022	$ 347
2023	330
2024	323
2025	316
2026	308
2027 - 2031	1,425
OPEB Plans
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2022	11
2023	10
2024	10
2025	9
2026	9
2027 - 2031	$ 38

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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=123447040&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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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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