Fair Value Measurements - Carrying Amount and Fair Values of the Company's Assets and Liabilities Measured on a Recurring Basis (Detail) - Recurring [Member] - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Carrying Amount [Member]
Non-derivatives:
Cash and cash equivalents	$ 64.3	$ 41.6
Short-term investments	5.5	4.7
Non-derivatives:
Long-term debt (including current portion)	139.0	139.4
Finance leases (including current portion)	3.0	2.2
Carrying Amount [Member] \| Derivatives (Level 1 Measurement) [Member] \| Foreign Currency Forward Exchange Contracts [Member]
Derivatives (Level 1 measurement):
Foreign currency forward exchange contracts	0.6	1.8
Carrying Amount [Member] \| Non-financial Assets and Liabilities (Level 3 Measurement) [Member]
Non-financial liabilities (Level 3 measurement):
Acquisition-related contingent consideration (including current portion)	72.2	95.2
Carrying Amount [Member] \| Non-financial Assets and Liabilities (Level 3 Measurement) [Member] \| Stock Equivalent Units [Member]
Non-financial liabilities (Level 3 measurement):
Stock equivalent units	5.4	7.2
Fair Value [Member]
Non-derivatives:
Cash and cash equivalents	64.3	41.6
Short-term investments	5.5	4.7
Non-derivatives:
Long-term debt (including current portion)	139.0	139.4
Finance leases (including current portion)	3.0	2.2
Fair Value [Member] \| Derivatives (Level 1 Measurement) [Member] \| Foreign Currency Forward Exchange Contracts [Member]
Derivatives (Level 1 measurement):
Foreign currency forward exchange contracts	0.6	1.8
Fair Value [Member] \| Non-financial Assets and Liabilities (Level 3 Measurement) [Member]
Non-financial liabilities (Level 3 measurement):
Acquisition-related contingent consideration (including current portion)	72.2	95.2
Fair Value [Member] \| Non-financial Assets and Liabilities (Level 3 Measurement) [Member] \| Stock Equivalent Units [Member]
Non-financial liabilities (Level 3 measurement):
Stock equivalent units	$ 5.4	$ 7.2

Business acquisition contingent consideration fair value.

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- Definition

Derivative liabilities.

+ References

No definition available.

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- Definition

Finance leases fair value disclosure.

+ References

No definition available.

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- Definition

Non-derivatives assets.

+ References

No definition available.

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- Definition

Non-derivatives liabilities.

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No definition available.

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- Definition

Non-financial liabilities.

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No definition available.

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- Definition

Stock equivalent units fair value disclosure.

+ References

No definition available.

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4D

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=SL51823488-111719

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226000-175313

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph a, f, g

-Article 7

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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