Stock-Based Compensation - Compensation Expense (Details) - USD ($)
$ in Thousands |
3 Months Ended |
9 Months Ended |
Sep. 30, 2019 |
Sep. 30, 2018 |
Sep. 30, 2019 |
Sep. 30, 2018 |
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |
|
|
|
|
| Total equity based compensation expense |
$ 8,110
|
$ 5,341
|
$ 21,351
|
$ 14,329
|
| Restricted stock awards |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |
|
|
|
|
| Total equity based compensation expense |
4,569
|
2,393
|
11,159
|
6,157
|
| Stock option awards |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |
|
|
|
|
| Total equity based compensation expense |
2,557
|
2,337
|
7,766
|
6,853
|
| Performance stock units |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |
|
|
|
|
| Total equity based compensation expense |
918
|
611
|
2,360
|
1,319
|
| Employee Stock [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |
|
|
|
|
| Total equity based compensation expense |
$ 66
|
$ 0
|
$ 66
|
$ 0
|