INVENTORIES AND SUPPLIES (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]
Oil and oil products	$ 62,563	$ 59,639
Supplies and drums	72,172	64,471
Solvent and solutions	9,639	10,100
Other	17,418	17,886
Total inventories and supplies	$ 161,792	$ 152,096