v3.3.1.900
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