Segment, Geographic, Product and Significant Customer Information - Long-lived Tangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 26, 2015
Long-lived tangible assets:
Total long-lived tangible assets	$ 44,226	$ 44,493
United States [Member]
Long-lived tangible assets:
Total long-lived tangible assets	42,688	42,581
Taiwan [Member]
Long-lived tangible assets:
Total long-lived tangible assets	818	1,056
South Korea [Member]
Long-lived tangible assets:
Total long-lived tangible assets	554	697
Japan [Member]
Long-lived tangible assets:
Total long-lived tangible assets	57	59
All Other [Member]
Long-lived tangible assets:
Total long-lived tangible assets	$ 109	$ 100