Segment, Geographic, Product and Significant Customer Information - Long-lived Tangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013
Long-lived tangible assets:
Total long-lived tangible assets	$ 49,633	$ 47,439
United States [Member]
Long-lived tangible assets:
Total long-lived tangible assets	47,729	44,775
Japan [Member]
Long-lived tangible assets:
Total long-lived tangible assets	71	125
South Korea [Member]
Long-lived tangible assets:
Total long-lived tangible assets	284	445
All other [Member]
Long-lived tangible assets:
Total long-lived tangible assets	$ 1,549	$ 2,094