OPERATING SEGMENT (Details) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2015
USD ($)
segment
|
Dec. 31, 2014
USD ($)
|
Dec. 31, 2013
USD ($)
|
|
| OPERATING SEGMENT | |||
| Number of reportable segments | segment | 1 | ||
| OPERATING SEGMENT | |||
| Revenues | $ 2,946,900 | $ 2,695,390 | $ 2,749,428 |
| Total long-term assets | 4,697,566 | 4,364,047 | |
| U.S. | |||
| OPERATING SEGMENT | |||
| Revenues | 2,940,011 | 2,688,230 | 2,741,717 |
| Total long-term assets | 4,697,372 | 4,363,804 | |
| Canada | |||
| OPERATING SEGMENT | |||
| Revenues | 6,889 | 7,160 | $ 7,711 |
| Total long-term assets | $ 194 | $ 243 | |