INVENTORIES AND SUPPLIES (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Oil and oil products	$ 35,484	$ 62,111
Supplies and drums	75,357	68,547
Solvent and solutions	9,742	9,355
Modular camp accommodations	14,738	15,776
Other	14,934	12,874
Total inventories and supplies	$ 150,255	$ 168,663