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		9 Months Ended
		Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Loss Earnings Per Share [Line Items]
Net loss - basic		$ (25,134)	$ (19,311)	$ (33,565)	$ (53,331)
Net loss - diluted		$ (25,134)	$ (19,311)	$ (33,565)	$ (53,331)
Weighted average shares outstanding - basic		411,150	408,417	410,786	407,489
Weighted average shares outstanding - diluted		411,150	408,417	410,786	407,489
Loss per share - basic	[1]	$ (0.06)	$ (0.05)	$ (0.08)	$ (0.13)
Loss per share - diluted	[1]	$ (0.06)	$ (0.05)	$ (0.08)	$ (0.13)

[1] Excluding the licensing revenue change in estimates and Medicaid change in estimate, both discussed in Note 7 – Revenue Recognition, net loss per share, basic and diluted, for the three months ended September 30, 2023 would have been $(0.06) and net loss per share for the nine months ended September 30, 2024 and 2023 would have been $(0.09) and $(0.19), respectively.