Expected Benefit Payments for Pension and Postretirement Plans (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
2013	$ 27.8
2014	25.9
2015	24.3
2016	24.6
2017	24.5
Next 5 years	127.4
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
2013	0.6
2014	0.5
2015	0.5
2016	0.5
2017	0.5
Next 5 years	$ 2.4

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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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- Definition

Amount of benefits expected to be paid in the fifth 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 fourth 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 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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