Employee Benefits - Estimated Future Benefit Payments (Detail) $ in Millions	Dec. 31, 2020 USD ($)
Supplemental Plan
Schedule of Pension Expected Future Benefit Payments [Line Items]
2021	$ 18.0
2022	20.0
2023	18.2
2024	11.6
2025	12.7
2026-2030	62.0
U.S. Plan \| Pension Plans, Defined Benefit
Schedule of Pension Expected Future Benefit Payments [Line Items]
2021	86.8
2022	88.9
2023	96.3
2024	96.4
2025	98.6
2026-2030	495.5
Non U.S. Plans \| Pension Plans, Defined Benefit
Schedule of Pension Expected Future Benefit Payments [Line Items]
2021	4.4
2022	4.3
2023	4.8
2024	5.0
2025	5.0
2026-2030	$ 32.4

Schedule of Pension Expected Future Benefit Payments [Line Items]

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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=118255775&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.

+ References

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

+ References

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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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