Income Taxes - Schedule of Loss before Income Taxes, Domestic and Foreign (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
United States (U.S.)	$ (80,972)	$ (55,087)	$ (22,015)
Non-U.S.	(40,492)	(52,060)	(58,285)
Loss before income taxes	$ (121,464)	$ (107,147)	$ (80,300)