Postretirement Benefit Plans - Estimated Future Benefit Payments (Detail) $ in Millions	Dec. 31, 2021 USD ($)
Qualified Defined Benefit Pension Plans
Expected Future Benefit Payment [Abstract]
2022	$ 1,980
2023	2,080
2024	2,160
2025	2,230
2026	2,290
2027 – 2031	11,700
Retiree Medical and Life Insurance Plans
Expected Future Benefit Payment [Abstract]
2022	140
2023	140
2024	140
2025	130
2026	130
2027 – 2031	$ 570

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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.

+ 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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