Stock-Based Compensation Expense (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 02, 2011 Years Year EmployeeGroup BusinessSegment OptionPlan	Oct. 03, 2010 Year	Oct. 02, 2011 Year Years EmployeeGroup BusinessSegment OptionPlan	Oct. 03, 2010 Year
Stock option activity
Outstanding as of December 31, 2010, Shares			4,318
Outstanding as of December 31, 2010, Weighted-Average Exercise Price			$ 20.05
Granted, Shares			986
Granted, Weighted-Average Exercise Price	$ 30.43		$ 30.43
Exercised, Shares			(1,351)
Exercised, Weighted-Average Exercise Price	$ 20.70		$ 20.70
Forfeited or expired, Shares			(67)
Forfeited or expired, Weighted-Average Exercise Price			$ 21.96
Outstanding as of October 2, 2011, Shares	3,886		3,886
Outstanding as of October 2, 2011, Weighted-Average Exercise Price	$ 22.46		$ 22.46
Outstanding as of October 2, 2011, Weighted-Average Remaining Contractual Term (in years)	7.2		7.2
Outstanding as of October 2, 2011, Aggregate Intrinsic Value	$ 21,850,000		$ 21,850,000
Exercisable as of October 2, 2011, Shares	1,305		1,305
Exercisable as of October 2, 2011, Weighted-Average Exercise Price	$ 20.39		$ 20.39
Exercisable as of October 2, 2011, Weighted-Average Remaining Contractual Term (in years)			4.9
Exercisable as of October 2, 2011, Aggregate Intrinsic Value	8,989,000		8,989,000
Weighted-average assumptions used in estimating the fair values of stock options granted
Risk-free rate	3.60%	3.20%	3.60%	3.40%
Expected dividend yield	1.00%	1.40%	1.00%	1.30%
Expected volatility	42.00%	44.00%	42.00%	44.00%
Expected term (in years)	5.2	5.3	5.4	5.3
Stock-based compensation expense
Stock-based compensation expense	1,520,000	1,278,000	5,829,000	1,672,000
Product cost of revenue [Member]
Stock-based compensation expense
Stock-based compensation expense	80,000	63,000	350,000	135,000
Service cost of revenue [Member]
Stock-based compensation expense
Stock-based compensation expense	27,000	32,000	136,000	44,000
Research, development, and engineering [Member]
Stock-based compensation expense
Stock-based compensation expense	394,000	346,000	1,732,000	680,000
Selling, general, and administrative [Member]
Stock-based compensation expense
Stock-based compensation expense	$ 1,019,000	$ 837,000	$ 3,611,000	$ 813,000