Stockholders' Equity - Restricted Stock Units - Additional Information (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | ||||
| Unrecognized stock compensation expense | $ 29.8 | $ 29.8 | ||
| Expected weighted average period to recognize unrecognized stock compensation expense | 1 year 10 months 24 days | |||
| Restricted Stock Units | ||||
| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | ||||
| Unrecognized stock compensation expense | 189.1 | $ 189.1 | ||
| Expected weighted average period to recognize unrecognized stock compensation expense | 3 years | |||
| Intrinsic value of restricted stock units vested during the period | $ 19.4 | $ 0.3 | $ 30.8 | $ 0.3 |