Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012
Revenue information shown by geographic region
Total revenues	$ 9,210	$ 8,445	$ 18,149	$ 16,750
United States
Revenue information shown by geographic region
Total revenues	4,962	4,442	9,171	8,664
Europe
Revenue information shown by geographic region
Total revenues	1,628	1,932	3,601	3,777
Rest of Americas
Revenue information shown by geographic region
Total revenues	941	626	1,791	1,328
Asia/Pacific Rim
Revenue information shown by geographic region
Total revenues	$ 1,679	$ 1,445	$ 3,586	$ 2,981