Stock-based Compensation - Summary of Company's Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2021
Number of Shares Subject to Options
Beginning balance (in shares)		63,267,000
Granted (in shares)	0	0
Cancelled (in shares)		(1,679,000)
Exercised (in shares)		(8,176,000)
Ending balance (in shares)	53,412,000	53,412,000	63,267,000
Exercisable (in shares)	38,496,000	38,496,000
Vested and expected to vest (in shares)	53,412,000	53,412,000
Weighted- Average Exercise Price
Beginning balance, weighted average exercise price (in dollars per share)		$ 2.82
Granted, weighted average exercise price (in dollars per share)		0
Cancelled, weighted average exercise price (in dollars per share)		4.01
Exercised, weighted average exercise price (in dollars per share)		2.41
Ending balance, weighted average exercise price (in dollars per share)	$ 2.84	2.84	$ 2.82
Exercisable, weighted average exercise price (in dollars per share)	2.29	2.29
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 2.84	$ 2.84
Remaining contractual tern		6 years 2 months 26 days	6 years 11 months 19 days
Exercisable, remaining contractual term		5 years 9 months 14 days
Vested and expected to vest, remaining contractual term		6 years 2 months 26 days
Aggregate intrinsic value	$ 1,762,455	$ 1,762,455	$ 6,348,395
Exercisable, aggregate intrinsic value	1,291,511	1,291,511
Vested and expected to vest, aggregate intrinsic value	$ 1,762,455	$ 1,762,455