Segment, Geographic, Product and Significant Customer Information - Revenue Net (Details) $ in Thousands	3 Months Ended
	Apr. 01, 2017 USD ($) segment	Mar. 26, 2016 USD ($)
Revenues From External Customers And Long Lived Assets [Line Items]
Number of operating segments | segment	1
Net revenues:
Total net revenues	$ 59,314	$ 47,489
South Korea [Member]
Net revenues:
Total net revenues	18,619	8,436
United States [Member]
Net revenues:
Total net revenues	13,573	7,191
Taiwan [Member]
Net revenues:
Total net revenues	11,833	5,477
China [Member]
Net revenues:
Total net revenues	6,687	6,506
Japan [Member]
Net revenues:
Total net revenues	3,353	7,188
Singapore [Member]
Net revenues:
Total net revenues	1,491	9,902
Other [Member]
Net revenues:
Total net revenues	$ 3,758	$ 2,789