Goodwill and Intangible Assets - Schedule of Intangible Assets Other Than Goodwill (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Intangible assets subject to amortization
Gross carrying amount	$ 238,867	$ 234,533
Accumulated amortization	(97,505)	(88,059)
Foreign currency translation adjustment	(8,254)	(8,249)
Total	133,108	138,225
Intangible assets with indefinite lives
Gross carrying amount	14,883	19,217
Foreign currency translation adjustment	(1,050)	(997)
Total	13,833	18,220
Total intangible assets, net	$ 146,941	$ 156,445