Postretirement Benefit Plans - Estimated Future Benefit Payments (Detail) $ in Millions	Dec. 31, 2022 USD ($)
Qualified Defined Benefit Pension Plans
Expected Future Benefit Payment [Abstract]
2023	$ 1,720
2024	1,810
2025	1,890
2026	1,950
2027	2,000
2028 – 2032	10,150
Retiree Medical and Life Insurance Plans
Expected Future Benefit Payment [Abstract]
2023	140
2024	130
2025	130
2026	120
2027	120
2028 – 2032	$ 530

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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 https://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.

+ References

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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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