Equity-Based Compensation (Schedule Of Equity-Based Compensation Expense) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 01, 2011	Jul. 02, 2010	Jul. 01, 2011	Jul. 02, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense before income taxes	$ 8.0	$ 7.4	$ 15.6	$ 13.2
Income tax benefit	(1.2)	(2.5)	(2.6)	(4.3)
Total equity-based compensation expense after income taxes	6.8	4.9	13.0	8.9
Cost Of Revenue - Products [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense before income taxes	0.5	0.6	1.0	1.0
Cost Of Revenue - Services [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense before income taxes	0.6	0.6	1.2	1.1
Research And Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense before income taxes	3.1	2.4	5.6	4.2
Sales And Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense before income taxes	1.3	1.3	2.6	2.5
General And Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense before income taxes	$ 2.5	$ 2.5	$ 5.2	$ 4.4