Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020 USD ($) $ / shares shares	Dec. 31, 2019 $ / shares shares
Number of Stock Options
Outstanding at the beginning of period (in shares) | shares	3,820
Granted (in shares) | shares	1,041
Exercised (in shares) | shares	(1,143)
Canceled or forfeited (in shares) | shares	(172)
Outstanding at the end of the period (in shares) | shares	3,546	3,820
Exercisable at the end of the period (in shares) | shares	1,843
Weighted- Average Exercise Price Per Share
Outstanding at the beginning of period (in dollars per share) | $ / shares	$ 36.26
Granted (in dollars per share) | $ / shares	62.88
Exercised (in dollars per share) | $ / shares	31.83
Canceled or forfeited (in dollars per share) | $ / shares	42.71
Outstanding at the end of the period (in dollars per share) | $ / shares	45.19	$ 36.26
Exercisable at the end of the period (in dollars per share) | $ / shares	$ 37.22
Weighted- Average Contractual Life (in years)
Outstanding at the beginning of the period	7 years 5 months 1 day	6 years 9 months 21 days
Outstanding at the end of the period	7 years 5 months 1 day	6 years 9 months 21 days
Exercisable at the end of the period	6 years 2 months 19 days
Aggregate Intrinsic Value
Outstanding at the end of the period | $	$ 238,802
Exercisable at the end of the period | $	138,783
Aggregate intrinsic value of options exercised | $	67,700
Unrecognized compensation expense | $	$ 44,100
Weighted-average period for recognition	2 years 7 months 9 days