Intangible Assets and Goodwill (Future Amortization) (Details) $ in Thousands  | 
 Sep. 30, 2018  
USD ($) 
 | 
|---|---|
| Years Ending December 31, | |
| Remainder of 2018 | $ 16,994 | 
| 2019 | 59,357 | 
| 2020 | 51,358 | 
| 2021 | 45,754 | 
| 2022 | $ 41,656 | 
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
  | 
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
  | 
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
  | 
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
  | 
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
  | 
| X | ||||||||||
- References No definition available. 
  |