Schedule of Equity Based Compensation Expense (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 29, 2013	Mar. 30, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense before income taxes	$ 3.1	$ 5.6
Income tax benefit	(0.1)	(0.1)
Total equity-based compensation expense after income taxes	3.0	5.5
Cost of Revenue - products
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense before income taxes	0.2	0.4
Cost of Revenue - services
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense before income taxes	0.4	0.5
Research and Development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense before income taxes	0.6	1.8
Sales And Marketing
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense before income taxes	0.5	0.9
General and Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Equity-based compensation expense before income taxes	$ 1.4	$ 2.0