Restructuring - Additional Information (Details) - USD ($)		9 Months Ended
Feb. 13, 2018	Sep. 30, 2018
Restructuring Cost And Reserve [Line Items]
Restructuring implementation date	Feb. 13, 2018
Percentage of employees affected under reduction in force program	9.00%
Restructuring charge		$ 3,749,000
Non-cash benefit, net		454,000
Cease-Use Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charge		2,538,000
Non-cash benefit, net		$ 454,000
The lease period of restructuring liability		2023-01

Restructuring liability amortised period.

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(a))
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- Definition

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.

+ Details

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- Definition

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.

+ References

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-Publisher FASB
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-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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