Segment, Geographic, Product and Significant Customer Information - Long-lived Tangible Assets (Details) - USD ($) $ in Thousands	Sep. 26, 2015	Dec. 27, 2014
Long-lived tangible assets:
Total long-lived tangible assets	$ 45,944	$ 49,633
United States [Member]
Long-lived tangible assets:
Total long-lived tangible assets	44,410	47,729
Taiwan [Member]
Long-lived tangible assets:
Total long-lived tangible assets	1,146	1,473
All other [Member]
Long-lived tangible assets:
Total long-lived tangible assets	$ 388	$ 431