Operating Segments and Related Information (Details 5) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 379,472	$ 344,517
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	194,300	166,500
Canada/Latin_America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	29,242	16,427
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	84,410	93,255
Mid_East/Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	27,712	26,567
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 43,825	$ 41,813