Stock Plans (Summary of Stock Option Activity) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	6 Months Ended
	Jul. 01, 2012 years
Stock option activity
Number of Shares, Outstanding at beginning of period	5,346
Number of Shares, Granted	740
Number of Shares, Exercised	(637)
Number of Shares, Canceled	(206)
Number of Shares, Forfeited	(5)
Number of Shares, Outstanding at end of period	5,238
Number of Shares, Exercisable at end of period	3,633
Number of Shares, Vested and expected to vest in the future	4,783
Weighted-Average Price, Outstanding at beginning of period	$ 20.57
Weighted-Average Price, Granted	$ 26.25
Weighted-Average Price, Exercised	$ 18.44
Weighted-Average Price, Canceled	$ 22.26
Weighted-Average Price, Forfeited	$ 14.76
Weighted-Average Price, Outstanding at end of period	$ 21.57
Weighted-Average Price, Exercisable at end of period	$ 20.34
Weighted-Average Price, Vested and expected to vest in the future	$ 21.57
Weighted-Average Remaining Contractual Term in Years, Outstanding at end of period	3.8
Weighted-Average Remaining Contractual Term in Years, Exercisable at end of period	2.8
Weighted-Average Remaining Contractual Term in Years, Vested and expected to vest in the future	3.8
Total Intrinsic Value, Outstanding at end of period	$ 25.8
Total Intrinsic Value, Exercisable at end of period	22.3
Total Intrinsic Value, Vested and expected to vest in the future	$ 23.5