Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (91,148)	$ (39,209)	$ (17,014)
Other comprehensive loss:
Unrealized loss on marketable securities, net of tax of $0	40	(181)
Foreign currency translation adjustments, net of tax of $0	(1,385)	(158)
Comprehensive loss	$ (92,493)	$ (39,548)	$ (17,014)