Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Jan. 01, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense, outstanding stock options	$ 13.3
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense, unvested restricted stock or RSUs	$ 115.3
Estimated remaining weighted average period	3 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated remaining weighted average period	1 year 6 months
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense, unvested restricted stock or RSUs	$ 0.4
Estimated remaining weighted average period	3 months 18 days
2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)		4,929,361
Shares available for grant (in shares)	17,836,584

Aggregate number of common shares reserved for future issuance.

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