v3.20.4

Postretirement Benefit Plans - Summary of Weighted Average Assumptions Used to Calculate Projected Benefit Obligations (Detail)	Dec. 31, 2020	Dec. 31, 2019
Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]
Discount rate	0.80%	1.20%
Rate of compensation increase	1.60%	1.50%

X

- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ 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 (k)(1)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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X

- Definition

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ 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 (k)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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Period Type:	instant

X

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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