Intangible Assets (Details Textual) - USD ($) |
6 Months Ended | |
|---|---|---|
Jun. 30, 2017 |
Jun. 30, 2016 |
|
| Intangible Assets (Textual) | ||
| Amortization expense | $ 2,059,000 | $ 1,970,000 |
| Amortization expense, excluding amortization of landfill assets | $ 136,000 | $ 1,757,000 |
| Minimum [Member] | ||
| Intangible Assets (Textual) | ||
| Useful life of intangible assets | 5 years | |
| Maximum [Member] | ||
| Intangible Assets (Textual) | ||
| Useful life of intangible assets | 20 years | |