Pension and Other Postretirement Benefits - Schedule of Benefit Payments Expected to be Paid (Detail) $ in Millions	Dec. 31, 2021 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2022	$ 285
2023	280
2024	285
2025	285
2026	285
2027 through 2031	1,365
Total benefit payments	2,785
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2022	60
2023	55
2024	55
2025	50
2026	50
2027 through 2031	215
Total benefit payments	$ 485

Defined Benefit Plan Expected Future Benefit Payments

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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

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- Definition

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

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

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

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

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

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