Segment, Geographic, Product and Significant Customer Information - Revenue Net (Details) $ in Thousands	3 Months Ended
	Mar. 26, 2016 USD ($) segment	Mar. 28, 2015 USD ($)
Revenues From External Customers And Long Lived Assets [Line Items]
Number of operating segments | segment	1
Net revenues:
Total net revenues	$ 47,489	$ 50,376
United States [Member]
Net revenues:
Total net revenues	7,191	9,078
South Korea [Member]
Net revenues:
Total net revenues	8,436	14,643
China [Member]
Net revenues:
Total net revenues	6,506	4,001
Taiwan [Member]
Net revenues:
Total net revenues	5,477	14,428
Singapore [Member]
Net revenues:
Total net revenues	9,902	2,794
Other [Member]
Net revenues:
Total net revenues	$ 9,977	$ 5,432