Postretirement Benefit Plans - Estimated Future Benefit Payments (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	$ 17.0
2016	17.6
2017	18.0
2018	18.4
2019	18.9
2020 – 2024	98.5
International Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	3.7
2016	3.6
2017	3.5
2018	3.7
2019	3.6
2020 – 2024	19.1
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	10.6
2016	10.3
2017	10.2
2018	10.0
2019	9.8
2020 – 2024	$ 43.1

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Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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=35743120&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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+ Details

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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