Goodwill, In-Process Research and Development and Intellectual Property - Summary of Gross Intellectual Property, Accumulated Amortization, and Net Intellectual Property (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Developed Technology
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 66,413	$ 66,413
Accumulated amortization	(38,272)	(30,550)
Foreign currency translation impact	1,838	3,495
Net carrying amount	29,979	39,358
Technology and Patents Purchased
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	400	400
Accumulated amortization	(104)	(72)
Foreign currency translation impact	14	30
Net carrying amount	310	358
Intellectual Property
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	66,813	66,813
Accumulated amortization	(38,376)	(30,622)
Foreign currency translation impact	1,852	3,525
Net carrying amount	$ 30,289	$ 39,716