Summary of Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) $ / shares shares
Stock Option Shares
Grants outstanding at beginning of the period | shares	7,844,947
Granted | shares	1,685,860
Exercised | shares	(283,622)
Cancelled and forfeited | shares	(1,050,264)
Grants outstanding at end of the period | shares	8,196,921
Grants exercisable at end of the period | shares	2,532,438
Grants vested and expected to vest at end of the period | shares	7,867,722
Weighted Average Exercise Price
Grants outstanding at beginning of the period | $ / shares	$ 70.61
Granted | $ / shares	86.41
Exercised | $ / shares	45.71
Cancelled and forfeited | $ / shares	112.18
Grants outstanding at end of the period | $ / shares	69.39
Grants exercisable at end of the period | $ / shares	84.71
Grants vested and expected to vest at end of the period | $ / shares	$ 68.17
Aggregate Intrinsic Value
Outstanding at end of year | $	$ 248,479
Exercisable at end of year | $	59,069
Vested and expected to vest | $	$ 247,434
Weighted Average Remaining Contractual Life (Years)
Outstanding at end of year	6 years 4 months 24 days
Exercisable at end of year	5 years 7 months 6 days
Vested and expected to vest	6 years 3 months 18 days