Stock-Based Compensation (Detail Of The Total Stock-Based Compensation Recognized By Income Statement Classification) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 68,320	$ 55,844	$ 133,554	$ 91,567
Cost of subscription, support and services revenues [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	2,956	2,241	5,158	3,721
Research and development [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	25,419	17,715	53,256	28,508
Sales, marketing and services [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	24,424	19,618	44,350	33,185
General and administrative [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 15,521	$ 16,270	$ 30,790	$ 26,153