Expected Benefit Payments (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
2014	$ 193.6
2015	194.9
2016	200.9
2017	209.2
2018	216.3
2019-2023	1,222.5
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
2014	33.8
2015	34.3
2016	34.8
2017	35.1
2018	35.6
2019-2023	176.6
Estimated Subsidy Reimbursements
Defined Benefit Plan Disclosure [Line Items]
2014	3.8
2015	4.1
2016	4.3
2017	4.7
2018	5.0
2019-2023	$ 31.0

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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 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.

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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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