Stock-based Compensation - Summary of Company's Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance (in shares)	63,267,000
Granted (in shares)	0
Cancelled (in shares)	(432,000)
Exercised (in shares)	(4,150,000)
Ending balance (in shares)	58,685,000	63,267,000
Exercisable (in shares)	35,468,000
Vested and expected to vest (in shares)	58,685,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
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)	3.74
Exercised, weighted average exercise price (in dollars per share)	2.48
Ending balance, weighted average exercise price (in dollars per share)	2.85	$ 2.82
Exercisable, weighted average exercise price (in dollars per share)	2.02
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 2.85
Remaining contractual tern	6 years 8 months 26 days	6 years 11 months 19 days
Exercisable, remaining contractual term	6 years 18 days
Vested and expected to vest, remaining contractual term	6 years 8 months 26 days
Aggregate intrinsic value	$ 2,547,170	$ 6,348,395
Exercisable, aggregate intrinsic value	1,569,430
Vested and expected to vest, aggregate intrinsic value	$ 2,547,170