Goodwill and Intangible Assets, Net, Carrying Amount of Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Goodwill
Balance at the beginning of the period	$ 130,250
Amortization	1,815
Foreign exchange	(353)
Balance at the end of the period	131,712	$ 138,026
Intangible Assets
Balance at the beginning of the period	24,402
Finite-lived Intangible Assets Acquired	1,213
Amortization	(1,337)	(1,300)
Foreign exchange	(130)
Balance at the end of the period	$ 24,148	$ 28,302