Financial Instruments and Hedging Activities (Quantitative Summary of Fair Value of Derivative Instruments) (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Sep. 30, 2014
Derivatives, Fair Value [Line Items]
Net asset (liability) value of non-hedged derivative instruments	$ (338)	$ (407)
Foreign currency contracts \| Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Asset value of non-hedge derivative instruments	379	0
Foreign currency contracts \| Accrued Expenses And Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	(383)	(272)
Security Price Guarantees \| Contingent and deferred acquisition payment [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	(334)	0
Security Price Guarantees \| Accrued Expenses And Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	$ 0	$ (135)

Derivative Instruments Not Designated as Hedging Instruments, at Fair Value, Net

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

+ Details

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

+ References

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