Operating Segments and Related Information (Details 5) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	$ 406,814	$ 379,472
United States
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	221,832	194,283
Europe [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	83,271	84,410
Asia [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	53,924	43,825
Mid_East/Africa [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	25,142	27,712
Canada/Latin_America [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	$ 22,645	$ 29,242