Segment Information (Geographic Information of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 260,178	$ 199,427
Operating Segments [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	260,178	199,427
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	135,563	112,083
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	65,809	41,492
Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	34,574	18,267
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 24,232	$ 27,585