Stock-Based Compensation (Detail Of The Total Stock-Based Compensation Recognized By Income Statement Classification) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 85,169	$ 68,969	$ 228,854	$ 202,523
Cost of subscription, support and services revenues [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	3,542	2,898	9,708	8,056
Research and development [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	28,803	25,505	81,386	78,761
Sales, marketing and services [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	28,411	23,838	76,640	68,188
General and administrative [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 24,413	$ 16,728	$ 61,120	$ 47,518