Share-based Compensation - Summary of RSU Activity (Details) - Time-vested RSUs - $ / shares |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Number of Shares | |||
| Unvested at the beginning of the period (in shares) | 2,266,286 | ||
| Granted (in shares) | 2,826,092 | ||
| Vested (in shares) | (791,484) | ||
| Forfeited (in shares) | (556,094) | ||
| Unvested at the end of the period (in shares) | 3,744,800 | 2,266,286 | |
| Weighted Average Grant Date Fair Value | |||
| Unvested at the beginning of the period (in dollars per share) | $ 55.32 | ||
| Granted (in dollars per share) | 30.47 | $ 63.01 | $ 54.85 |
| Vested (in dollars per share) | 53.62 | ||
| Forfeited (in dollars per share) | 41.44 | ||
| Unvested at the end of the period (in dollars per share) | $ 38.99 | $ 55.32 | |