Segment, Geographic, Product and Significant Customer Information - Revenue Net (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 25, 2016 USD ($)	Jun. 27, 2015 USD ($)	Jun. 25, 2016 USD ($) segment	Jun. 27, 2015 USD ($)
Revenues From External Customers And Long Lived Assets [Line Items]
Number of operating segments | segment			1
Net revenues:
Total net revenues	$ 55,767	$ 48,629	$ 103,256	$ 99,005
United States [Member]
Net revenues:
Total net revenues	8,904	15,052	16,095	24,130
South Korea [Member]
Net revenues:
Total net revenues	4,468	7,370	12,904	22,013
China [Member]
Net revenues:
Total net revenues	13,009	10,090	19,515	12,887
Taiwan [Member]
Net revenues:
Total net revenues	5,151	9,414	10,629	23,842
Singapore [Member]
Net revenues:
Total net revenues	16,617	1,625	26,519	5,626
Other [Member]
Net revenues:
Total net revenues	$ 7,618	$ 5,078	$ 17,594	$ 10,507