Stock-based compensation - Summary of Stock Option Activity Under Plan (Detail) shares in Thousands	3 Months Ended
	Mar. 31, 2022 $ / shares shares
Shares (in thousands)
Outstanding at beginning of period (in shares) | shares	3,586
Granted (in shares) | shares	890
Exercised (in shares) | shares	(1)
Canceled or forfeited (in shares) | shares	(735)
Outstanding at end of period (in shares) | shares	3,740
Exercisable at end of period (in shares) | shares	1,406
Vested and expected to vest at end of period (in shares) | shares	3,740
Weighted- average exercise price per share
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 39.23
Granted (in dollars per share) | $ / shares	7.79
Exercised (in dollars per share) | $ / shares	1.04
Canceled or forfeited (in dollars per share) | $ / shares	58.27
Outstanding at end of period (in dollars per share) | $ / shares	29.14
Exercisable at end of period (in dollars per share) | $ / shares	52.80
Vested and expected to vest at end of period (in dollars per share) | $ / shares	$ 29.14