Net Loss Per Share - Schedule of Net Ioss Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Net loss - basic and diluted	$ (102,115)	$ (41,818)
Weighted-average common shares outstanding:
Basic and diluted	91,056	89,526
Net loss per share:
Basic and diluted	$ (1.12)	$ (0.47)

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

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