Stock Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Share-based compensation expense and allocation by cost [Line Items]
Share-based Compensation	$ 36,090	$ 29,998	$ 94,008	$ 79,986
Cost of product and maintenance
Share-based compensation expense and allocation by cost [Line Items]
Share-based Compensation	612	550	1,632	1,461
Cost of services
Share-based compensation expense and allocation by cost [Line Items]
Share-based Compensation	895	807	2,373	2,141
Marketing and sales
Share-based compensation expense and allocation by cost [Line Items]
Share-based Compensation	7,422	6,040	19,667	16,881
Research and development
Share-based compensation expense and allocation by cost [Line Items]
Share-based Compensation	21,792	18,002	55,288	46,376
General and administrative
Share-based compensation expense and allocation by cost [Line Items]
Share-based Compensation	$ 5,369	$ 4,599	$ 15,048	$ 13,127