Equity Incentive Plans and Employee Stock Purchase Plan - Employee Stock Purchase Plan (Details) - shares |
1 Months Ended | 3 Months Ended |
|---|---|---|
Oct. 31, 2017 |
Apr. 30, 2018 |
|
| Class A Common Stock | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Shares issued (in shares) | 0 | |
| Employee Stock Purchase Plan | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Maximum employee contribution rate | 15.00% | |
| Duration of separate offering periods | 6 months | |
| Purchase price of common stock, as a percent | 85.00% | |
| Employee Stock Purchase Plan | Class A Common Stock | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Reserved for future issuance (in shares) | 1,500,000 |