Segment and Geographic Information - Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 481,208	$ 429,878	$ 419,972	$ 449,800	$ 480,205	$ 435,412	$ 416,629	$ 447,576	$ 1,780,858	$ 1,779,822	$ 1,088,377
Long-Lived Assets	300,883				284,386				300,883	284,386	307,736
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									1,224,135	1,292,492	671,511
Long-Lived Assets	226,358				227,659				226,358	227,659	257,939
Mexico
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									531,744	464,161	397,549
Long-Lived Assets	65,260				53,175				65,260	53,175	47,243
Other Latin America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									24,979	23,169	19,317
Long-Lived Assets	$ 9,265				$ 3,552				$ 9,265	$ 3,552	$ 2,554