Date the restructuring activities were initiated or are expected to be initiated, in CCYY-MM-DD format.

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

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-Name Accounting Standards Codification
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-Section S99
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- Definition

The number of positions eliminated during the period as a result of restructuring activities.

+ References

No definition available.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

+ References

No definition available.

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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- Definition

Restructuring plan notification date to affected employees.

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Subsequent Event - Additional Information (Detail) - Restructuring Plan [Member] $ in Millions		1 Months Ended	3 Months Ended
	May 03, 2018 Employee	Oct. 31, 2017	Jun. 30, 2018 USD ($)
Subsequent Event [Line Items]
Restructuring plan effective date		Oct. 20, 2017
Scenario, Forecast [Member]
Subsequent Event [Line Items]
One-time severance-related charge \| $			$ 3.0
Subsequent Event [Member]
Subsequent Event [Line Items]
Number of employees reduced \| Employee	13
Approximate reduction as a percent of workforce	48.00%
Restructuring plan notification date to affected employees	May 03, 2018