Other Post-Employment Benefits and Other Employee Benefit Plans - Estimated Future Benefit Payments (Detail) $ in Millions	Dec. 31, 2018 USD ($)
Defined Benefit Plan Disclosure [Line Items]
2019	$ 39.9
2020	36.5
2021	38.9
2022	39.5
2023	38.8
2024 to 2028 (combined)	209.0
Total	402.6
Other Post-Employment Benefits and Other Employee Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
2019	5.4
2020	5.4
2021	5.0
2022	4.6
2023	4.3
2024 to 2028 (combined)	15.6
Total	$ 40.3

Defined benefit plan expected future benefit payments.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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.

+ References

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- Definition

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

+ References

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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.

+ References

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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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