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, 2023	Mar. 31, 2022
Loss Earnings Per Share [Line Items]
Net loss-basic and diluted	$ (16,460)	$ (31,563)
Weighted average shares outstanding-basic	406,177	397,805
Weighted average shares outstanding-diluted	406,177	397,805
Net loss per share-basic	$ (0.04)	$ (0.08)
Net loss per share-diluted	$ (0.04)	$ (0.08)