Goodwill and Intangible Assets - Schedule of Intangible Assets Other Than Goodwill (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Intangible assets subject to amortization
Gross carrying amount	$ 238,867	$ 234,533
Accumulated amortization	(101,923)	(88,059)
Foreign currency translation adjustment	(8,265)	(8,249)
Total	128,679	138,225
Intangible assets with indefinite lives
Gross carrying amount	14,883	19,217
Foreign currency translation adjustment	(1,075)	(997)
Total	13,808	18,220
Total intangible assets, net	$ 142,487	$ 156,445