Estimated Future Benefits Payments for Retirement Plans (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Pension Plans
Schedule Of Other Retirement Benefits Expected Benefit Payments [Line Items]
2016	$ 10.3
2017	10.9
2018	39.6
2019	14.0
2020 - 2024	110.5
2015	8.3
Other Retirement Plans
Schedule Of Other Retirement Benefits Expected Benefit Payments [Line Items]
2016	1.0
2017	1.1
2018	1.3
2019	1.5
2020 - 2024	9.6
2015	$ 0.8

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

+ 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=28361610&loc=d3e1928-114920

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- Definition

Amount of benefits expected to be paid in the remainder of the fiscal year following the latest fiscal year ended from a defined benefit plan.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

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

+ References

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

+ References

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

+ References

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