Restructuring Charges - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Restructuring And Related Activities [Abstract]
Restructuring charges		$ 0	$ 0	$ 476,000
Percentage of eliminated work force				6.00%
Pre-Tax restructuring charges	$ 500,000

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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

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-Name Accounting Standards Codification

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

-Publisher FASB

-Name Accounting Standards Codification

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

-Publisher FASB

-Name Accounting Standards Codification

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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