Stockholders' Equity - Schedule of Reserved Shares of Common Stock for Future Issuances (Details) shares in Thousands |
Jun. 30, 2019
shares
|
|---|---|
| Class Of Stock [Line Items] | |
| Total reserved shares of common stock | 36,874 |
| Equity Incentive Plan | |
| Class Of Stock [Line Items] | |
| Common stock awards granted under equity incentive plans | 16,595 |
| Employee Stock Purchase Plan | |
| Class Of Stock [Line Items] | |
| Common stock awards available for issuance | 2,089 |
| 2017 Plan | |
| Class Of Stock [Line Items] | |
| Common stock awards available for issuance | 18,190 |