Equipment and Leasehold Improvements (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 29, 2012	Dec. 30, 2011
Plant, equipment and leasehold improvements
Plant, equipment and leasehold improvements, Gross	$ 19,050	$ 17,255
Less: accumulated depreciation and amortization	(12,710)	(11,876)
Property, Plant and Equipment, Net, Total	6,340	5,379
Machinery and equipment [Member]
Plant, equipment and leasehold improvements
Plant, equipment and leasehold improvements, Gross	5,613	5,598
Machinery and equipment [Member] | Minimum [Member]
Plant, equipment and leasehold improvements
Plant, Equipment and leasehold improvements useful lives	5 years
Machinery and equipment [Member] | Maximum [Member]
Plant, equipment and leasehold improvements
Plant, Equipment and leasehold improvements useful lives	10 years
Computers, data processing and other equipment [Member]
Plant, equipment and leasehold improvements
Plant, equipment and leasehold improvements, Gross	4,658	3,941
Computers, data processing and other equipment [Member] | Minimum [Member]
Plant, equipment and leasehold improvements
Plant, Equipment and leasehold improvements useful lives	3 years
Computers, data processing and other equipment [Member] | Maximum [Member]
Plant, equipment and leasehold improvements
Plant, Equipment and leasehold improvements useful lives	7 years
Leasehold improvements [Member]
Plant, equipment and leasehold improvements
Plant, equipment and leasehold improvements, Gross	6,781	5,622
Leasehold improvements [Member] | Minimum [Member]
Plant, equipment and leasehold improvements
Plant, Equipment and leasehold improvements useful lives	7 years
Leasehold improvements [Member] | Maximum [Member]
Plant, equipment and leasehold improvements
Plant, Equipment and leasehold improvements useful lives	15 years
Furniture and fixtures [Member]
Plant, equipment and leasehold improvements
Plant, equipment and leasehold improvements, Gross	562	557
Plant, Equipment and leasehold improvements useful lives	7 years
Vehicles [Member]
Plant, equipment and leasehold improvements
Plant, equipment and leasehold improvements, Gross	501	496
Plant, Equipment and leasehold improvements useful lives	5 years
Other [Member]
Plant, equipment and leasehold improvements
Plant, equipment and leasehold improvements, Gross	85	85
Plant, Equipment and leasehold improvements useful lives	7 years
Construction-in-progress [Member]
Plant, equipment and leasehold improvements
Plant, equipment and leasehold improvements, Gross	$ 850	$ 956