Stock-Based Compensation Expense - Summary of Stock Option Activity (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares
Shares
Beginning balance outstanding | shares	12,899
Granted | shares	1,245
Exercised | shares	(4,565)
Forfeited or expired | shares	(609)
Ending balance outstanding | shares	8,970
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Beginning balance outstanding, weighted-average exercise price | $ / shares	$ 37.95
Granted, weighted-average exercise price | $ / shares	54.68
Exercised, weighted-average exercise price | $ / shares	27.54
Forfeited or expired, weighted-average exercise price | $ / shares	50.28
Ending balance outstanding, weighted-average exercise price | $ / shares	$ 44.73
Exercisable, Shares | shares	3,135
Options vested or expected to vest | shares	8,235
Exercisable, weighted-average exercise price | $ / shares	$ 33.79
Options vested or expected to vest, weighted-average exercise price | $ / shares	$ 44.08
Outstanding, weighted-average remaining contractual term (in years)	7 years 1 month 9 days
Exercisable, weighted-average remaining contractual term (in years)	5 years 7 months 6 days
Options vested or expected to vest, weighted-average remaining contractual term (in years)	7 years 3 days
Outstanding, aggregate intrinsic value | $	$ 318,873
Exercisable, aggregate intrinsic value | $	145,735
Options vested or expected to vest, aggregate intrinsic value | $	$ 298,118