Segment and Geographical Information - Segment Reporting Information by Segment (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
Jul. 01, 2017 |
Jun. 25, 2016 |
Jul. 01, 2017 |
Jun. 25, 2016 |
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| Segment Reporting Information [Line Items] | ||||||
| Revenue | [1] | $ 41,972 | $ 38,184 | $ 85,338 | $ 77,450 | |
| United States | ||||||
| Segment Reporting Information [Line Items] | ||||||
| Revenue | 38,336 | 34,789 | 78,178 | 70,700 | ||
| Non-US | ||||||
| Segment Reporting Information [Line Items] | ||||||
| Revenue | $ 3,636 | $ 3,395 | $ 7,160 | $ 6,750 | ||
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