Stock-Based Compensation (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011
Schedule of stock-based compensation expenses
Stock-based compensation expense	$ 1,878	$ 1,151	$ 4,092	$ 3,170
Cost of sales [Member]
Schedule of stock-based compensation expenses
Stock-based compensation expense	184	99	301	221
Selling, general and administrative expenses [Member]
Schedule of stock-based compensation expenses
Stock-based compensation expense	1,469	929	3,308	2,597
Research and development expense [Member]
Schedule of stock-based compensation expenses
Stock-based compensation expense	$ 225	$ 123	$ 483	$ 352