Share Based Compensation - Restricted Stock Awards (Details) - Restricted shares - $ / shares |
3 Months Ended | 9 Months Ended | |
|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2018 |
Sep. 30, 2017 |
|
| Avg wtd grant-date fair value | |||
| Unvested at beginning of period | $ 11.82 | $ 9.48 | |
| Granted | 13.81 | 13.51 | |
| Vested | 10.48 | 7.99 | |
| Forfeited | 8.81 | ||
| Unvested at end of period | $ 13.18 | $ 13.18 | $ 11.82 |
| Units | |||
| Unvested at beginning of period | 1,293,107 | 1,018,228 | |
| Granted (in shares) | 1,904,595 | 623,165 | |
| Vested (in shares) | (209,765) | (339,701) | |
| Forfeited (in shares) | (8,585) | ||
| Unvested at end of period | 2,987,937 | 2,987,937 | 1,293,107 |
| 2018 Plan | |||
| Units | |||
| Granted (in shares) | 209,654 | 225,852 | |
| Vested (in shares) | (6,771) | ||
| Director Plan | |||
| Avg wtd grant-date fair value | |||
| Unvested at beginning of period | $ 5.71 | ||
| Vested | $ 5.71 | ||
| Units | |||
| Unvested at beginning of period | 49,230 | ||
| Vested (in shares) | (49,230) | ||