Employee Benefits - Estimated Future Benefit Payments (Detail) $ in Millions	Dec. 31, 2018 USD ($)
Supplemental Plan
Schedule of Pension Expected Future Benefit Payments [Line Items]
2019	$ 12.0
2020	11.5
2021	14.4
2022	16.2
2023	14.9
2024-2028	63.6
U.S. Plan \| Pension Plans, Defined Benefit
Schedule of Pension Expected Future Benefit Payments [Line Items]
2019	74.0
2020	76.8
2021	75.1
2022	73.4
2023	77.1
2024-2028	368.9
Non U.S. Plans \| Pension Plans, Defined Benefit
Schedule of Pension Expected Future Benefit Payments [Line Items]
2019	3.4
2020	3.8
2021	4.1
2022	3.9
2023	4.3
2024-2028	$ 26.4

Schedule of Pension Expected Future Benefit Payments [Line Items]

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- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

+ References

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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