Significant Accounting Policies - Calculation of Net Loss and Number of Shares Used to Compute Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Loss Per Share [Line Items]
Net loss-basic and diluted	$ (31,563)	$ (1,626)
Weighted average shares outstanding-basic and diluted	397,805	394,638
Net loss per share-basic and diluted	$ (0.08)	$ (0.00)