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Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of shares as percentage of common shares outstanding | 5.00% |
Award vesting period | 4 years |
Number of shares reserved for future issuance (in shares) | 12,448,841 |
Accrued and other liabilities, related to shares held by employees and directors that were subject to repurchase | $ 2.8 | $ 5.3
Other long term liabilities, related to shares held by employees and directors that were subject to repurchase | $ 3.2 | $ 6.1
Stock Option |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Award vesting period | 4 years |
Stock options to purchase common stock |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Grants in period, weighted average grant date fair value (in dollars per share) | $ 18.41 |
Unrecognized stock based compensation expense | $ 98.2 |
Unrecognized stock based compensation expense, weighted average recognition period | 3 years 45 days |
Restricted Stock Unit |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Unrecognized stock based compensation expense | $ 55.3 |
Unrecognized stock based compensation expense, weighted average recognition period | 3 years 133 days |
Maximum |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Stock option grant period | 10 years |
Option exercise price as percentage of fair value of common stock on grate date | 100.00% |

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