Estimated Future Payments (Detail) $ in Millions	Dec. 31, 2017 USD ($)
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
2018	$ 60.5
2019	66.6
2020	68.5
2021	59.3
2022	58.6
2023 - 2027	285.6
Post-Retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
2018	0.3
2019	0.4
2020	0.4
2021	0.4
2022	0.4
2023 - 2027	$ 2.2

Defined Benefit Plan, Expected Future Benefit Payments in Year Six Through Ten

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- Definition

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+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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.

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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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