Net Loss per Share - Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Basic and diluted net loss per share calculation:
Numerator - net loss	$ (13,591)	$ (32,863)
Denominator - weighted average ordinary shares outstanding	190,072,112	172,789,209
Basic and diluted net loss per share	$ (0.07)	$ (0.19)

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

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