Pension and Other Postretirement Benefits - Schedule of Benefit Payments Expected to be Paid (Detail) $ in Millions	Dec. 31, 2023 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2024	$ 180
2025	175
2026	175
2027	180
2028	175
2029 through 2033	855
Total benefit payments	1,740
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2024	50
2025	50
2026	45
2027	45
2028	45
2029 through 2033	195
Total benefit payments	$ 430

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
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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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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