Stock-Based Compensation (Stock-Based Compensation Expense) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 116,190	$ 83,346	$ 53,154
Related income tax benefits	(47,454)	(34,518)	(20,503)
Stock-based compensation expense, net of taxes	$ 68,736	$ 48,828	$ 32,651
Basic earnings per share	$ (0.82)	$ (0.58)	$ (0.38)
Diluted earnings per share	$ (0.80)	$ (0.57)	$ (0.38)
Software Licenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 0	$ 0	$ 969
Maintenance and service
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	8,494	5,224	2,533
Selling, General And Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	60,639	47,099	30,817
Research And Development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 47,057	$ 31,023	$ 18,835