Revenue Recognition (Disaggregation of Revenue by Principal Geographic Area, Based on Customers' Domiciles) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Total revenue	$ 810,421	$ 721,789	$ 2,414,270	$ 1,985,717
United States
Disaggregation of Revenue [Line Items]
Total revenue	514,343	454,836	1,502,219	1,257,617
Europe, the Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenue	167,956	147,193	510,759	400,928
Asia Pacific Region
Disaggregation of Revenue [Line Items]
Total revenue	78,239	77,401	246,645	212,663
Canada
Disaggregation of Revenue [Line Items]
Total revenue	32,813	28,710	105,608	78,314
Latin America
Disaggregation of Revenue [Line Items]
Total revenue	$ 17,070	$ 13,649	$ 49,039	$ 36,195