v3.8.0.1

Description of Business and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 30, 2017
Entity Information [Line Items]
Accumulated deficit	$ (174,315)		$ (177,145)
Minimum
Entity Information [Line Items]
Fiscal period duration	364 days
Maximum
Entity Information [Line Items]
Fiscal period duration	371 days
Accounting Standards Update 2014-09
Entity Information [Line Items]
Accumulated deficit		$ 100
Difference between Revenue Guidance in Effect before and after Topic 606
Entity Information [Line Items]
Accumulated deficit	$ 59

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(a)(4))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30)(a)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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