Geographic and Significant Customer Information (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 27, 2014	Dec. 28, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived tangible assets	$ 50,736	$ 47,439
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived tangible assets	50,061	44,775
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived tangible assets	82	125
South Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived tangible assets	337	445
All Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived tangible assets	$ 256	$ 2,094