Segment Reporting (Narrative) (Details) |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
|
Jun. 30, 2018
USD ($)
|
Jun. 30, 2017
USD ($)
|
Jun. 30, 2018
USD ($)
segment
|
Jun. 30, 2017
USD ($)
|
Dec. 31, 2017
USD ($)
|
|
| Segment Reporting Information [Line Items] | |||||
| Number of business segments | segment | 2 | ||||
| Total revenues | $ 126,589,000 | $ 162,766,000 | $ 265,556,000 | $ 312,653,000 | |
| Foreign Locations [Member] | |||||
| Segment Reporting Information [Line Items] | |||||
| Total revenues | 0 | $ 0 | |||
| Long lived assets | $ 0 | $ 0 | $ 0 | ||