Stockholders' Equity - Stock Option Plan - Additional Information (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Sep. 30, 2020 |
Sep. 30, 2019 |
|
| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||||
| Intrinsic value of stock options exercised | $ 149.9 | $ 137.5 | $ 269.6 | $ 383.0 |
| Unrecognized stock compensation expense | $ 58.6 | $ 58.6 | ||
| Expected weighted average period to recognize unrecognized stock compensation expense | 1 year 10 months 2 days | |||