Employee Benefits - Information for Pension Plans with Accumulated Benefit Obligation in Excess of Plan Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Retirement Benefits [Abstract]
Accumulated benefit obligation	$ 456	$ 22,116
Fair value of plan assets	0	20,064
Projected benefit obligation	456	22,178
Fair value of plan assets	$ 0	$ 20,064

No definition available.

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- Definition

Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

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- Definition

Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
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