Employee Benefit Plans, Share Based Compensation by Cost and Expense Categories (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	$ 51.8	$ 46.0
Stock Options [Member]
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	1.2	2.2
RSUs, RSAs, and PSAs [Member]
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	46.8	40.6
ESPP [Member]
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	3.8	3.2
Cost of Revenues, Product [Member]
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	1.9	1.7
Cost of Revenues, Service [Member]
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	3.5	3.4
Research and Development [Member]
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	32.3	30.7
Sales and Marketing [Member]
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	9.4	5.8
General and Administrative [Member]
Stock Based Compensation Expense Recorded in Cost and Expense Categories
Share-based compensation expense	$ 4.7	$ 4.4