Segment Information Revenues By Region (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues from External Customers [Line Items]
Revenues		$ 635,037	$ 585,890	$ 1,249,613	$ 1,193,111
United States and Canada [Member]
Revenues from External Customers [Line Items]
Revenues		417,909	348,101	815,475	704,033
Europe, Middle East, and Africa [Member]
Revenues from External Customers [Line Items]
Revenues		167,314	184,748	338,556	386,822
Other [Member]
Revenues from External Customers [Line Items]
Revenues	[1]	$ 49,814	$ 53,041	$ 95,582	$ 102,256

[1] Other includes our operations in Latin America and Asia Pacific.