| Benefit Plans - Other Plans (Details) | 3 Months Ended | 
|---|---|
| Mar. 31, 2019  plan | |
| Retirement Benefits [Abstract] | |
| Number of other share-based benefit plans | 6 | 
| X | ||||||||||
| 
- Definition Share-based compensation arrangement by share-based payment award, number of share-based benefit plans. No definition available. 
 | 
| X | ||||||||||
| 
- References No definition available. 
 |