Segment Information (Revenues by geographic region) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Revenues, net	$ 601,138	$ 522,093	$ 1,269,820	$ 1,046,647
United States
Segment Reporting Information [Line Items]
Revenues, net	472,258	383,610	1,036,083	832,760
Europe
Segment Reporting Information [Line Items]
Revenues, net	78,056	107,231	153,942	157,014
Other Geographic Locations
Segment Reporting Information [Line Items]
Revenues, net	$ 50,824	$ 31,252	$ 79,795	$ 56,873