Shareholders' Equity (Summary Of Stock-Based Compensation Expense, Net Of Tax) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 02, 2015	Oct. 03, 2014	Oct. 02, 2015	Oct. 03, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 12.8	$ 11.0	$ 37.3	$ 32.1
Cost Of Sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	1.0	0.8	2.9	2.3
Research And Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	2.1	1.6	6.4	4.8
Sales And Marketing Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	2.2	2.0	6.7	6.0
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	7.5	6.6	21.3	19.0
Total Operating Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 11.8	$ 10.2	$ 34.4	$ 29.8