PROPERTY, PLANT AND EQUIPMENT - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 3,539,804	$ 3,332,595
Less - accumulated depreciation and amortization	1,945,811	1,770,617
Total property, plant and equipment, net	1,593,993	1,561,978
Land
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	134,809	123,734
Asset retirement costs (non-landfill)
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	15,349	15,148
Landfill assets
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	172,453	154,918
Buildings and improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	485,686	440,188
Camp equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	156,786	152,998
Vehicles
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	786,575	721,735
Equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	1,745,483	1,697,490
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	5,373	5,453
Construction in progress
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 37,290	$ 20,931