Restructuring - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2017	Jun. 30, 2017
Restructuring Cost [Line Items]
Restructuring Charges		$ 472,000
U.K. [Member]
Restructuring Cost [Line Items]
Extended lease term expiration date		Nov. 30, 2016
Restructuring Charges		$ 472,000
Discretionary termination benefits		273,000
Other restructuring costs		$ 199,000
Increase in stock-based compensation expense to account for the extension of the exercise period of all vested stock options	$ 99,000
Reduction of stock-based compensation to account for forfeitures of non-vested stock options	$ 133,000

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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Data Type:	xbrli:monetaryItemType
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