Segment and Geographic Information - Narrative (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment									1
Property and equipment, net	$ 910,618				$ 862,535				$ 910,618	$ 862,535
Revenue	713,363	$ 669,628	$ 662,759	$ 668,724	658,470	$ 624,440	$ 605,832	$ 600,293	2,714,474	2,489,035	$ 2,347,988
United States
Segment Reporting Information [Line Items]
Property and equipment, net	331,500				311,700				331,500	311,700
Revenue									1,683,272	1,637,198	1,629,298
Non-U.S.
Segment Reporting Information [Line Items]
Property and equipment, net	$ 235,700				$ 249,800				235,700	249,800
Revenue									$ 1,031,200	$ 855,000	$ 720,000
Sales | Geographic Concentration Risk | United States
Segment Reporting Information [Line Items]
Concentration risk percent (more than)									10.00%	10.00%	10.00%