Segment Information (Revenues by geographic region) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Revenues, net	$ 632,165	$ 519,550	$ 1,901,985	$ 1,566,197
United States
Segment Reporting Information [Line Items]
Revenues, net	512,062	399,597	1,548,145	1,232,357
Europe
Segment Reporting Information [Line Items]
Revenues, net	84,415	89,088	238,357	252,724
Other Geographic Locations
Segment Reporting Information [Line Items]
Revenues, net	$ 35,688	$ 30,865	$ 115,483	$ 81,116