Reconciliation Of Changes In Unrecognized Tax Benefits (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Unrecognized Tax Benefits [Line Items]
Balance at January 1	$ 26.3us-gaap_UnrecognizedTaxBenefits	$ 29.2us-gaap_UnrecognizedTaxBenefits	$ 24.3us-gaap_UnrecognizedTaxBenefits
Additions based on tax positions related to the current year	14.4	(2.4)	3.5
Changes for tax positions of prior years	(1.4)	(0.1)	1.4
Reductions as a result of a lapse of applicable statute of limitations	(1.6)		(0.4)
Settlements	(0.9)	(0.2)	(0.7)
Changes due to foreign currency	(1.8)	(0.2)	1.1
Balance at December 31	$ 35.0us-gaap_UnrecognizedTaxBenefits	$ 26.3us-gaap_UnrecognizedTaxBenefits	$ 29.2us-gaap_UnrecognizedTaxBenefits

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Unrecognized Tax Benefits, Increases (Decreases) Resulting From Current Period Tax Positions

+ References

No definition available.

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- Definition

Unrecognized Tax Benefits, Increases (Decreases) Resulting From Foreign Currency Translation

+ References

No definition available.

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- Definition

Unrecognized Tax Benefits, Increases (Decreases) Resulting from Prior Period Tax Positions

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No definition available.

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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- Definition

Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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- Definition

Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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