Net Loss per Share - Computation of Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net loss	$ (28,922)	$ (21,960)
Weighted-average common shares outstanding:
Basic and Diluted	46,724,951	39,552,277
Net loss per share, Basic and Diluted	$ (0.62)	$ (0.56)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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