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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