Expected Benefit Payments for Pension and Postretirement Plans (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013 Pension Benefits	Dec. 31, 2012 Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
2014	$ 26.8	$ 0.5
2015	25.5	0.5
2016	25.2	0.5
2017	25.1	0.5
2018	24.9	0.5
Next 5 years	$ 127.4	$ 2.3

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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=21915506&loc=d3e1928-114920

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- Definition

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

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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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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.

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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.

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