Stock Plans and Stock-Based Compensation - Summary of Option Activity Includes Options Granted (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares
Shares Subject to Outstanding Options
Beginning balance | shares	4,738,004
Options granted | shares	5,784,550
Options exercised | shares	(392,523)
Options forfeited or canceled | shares	(237,334)
Ending balance | shares	9,892,697
Options vested and expected to vest as of December 31, 2020 | shares	9,892,697
Options exercisable as of December 31, 2020 | shares	2,793,050
Weighted Average Exercise Price Per Share
Beginning balance | $ / shares	$ 9.00
Options granted | $ / shares	17.36
Options exercised | $ / shares	8.54
Options forfeited or canceled | $ / shares	10.38
Ending balance | $ / shares	13.88
Options vested and expected to vest as of December 31, 2020 | $ / shares	13.88
Options exercisable as of December 31, 2020 | $ / shares	$ 10.28
Weighted Average Remaining Contractual Term (in years)	8 years 9 months 21 days
Options vested and expected to vest, Weighted Average Remaining Contractual Term (in years)	8 years 9 months 21 days
Options exercisable, Weighted Average Remaining Contractual Term (in years)	8 years 1 month 13 days
Aggregate Intrinsic Value | $	$ 122,232
Options vested and expected to vest, Aggregate Intrinsic Value | $	122,232
Options exercisable, Aggregate Intrinsic Value | $	$ 44,012