PROPERTY, PLANT AND EQUIPMENT

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

PROPERTY, PLANT AND EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT

A summary of property, plant and equipment is as follows:

	December 31,
	2017			2016
Land	$	24,224		$	24,517
Landfills	513,548			570,464
Landfill operating lease contracts	114,462			133,239
Buildings and improvements	140,155			143,036
Machinery and equipment	139,029			132,748
Rolling stock	138,102			133,840
Containers	103,501			97,744
	1,173,021			1,235,588
Less: accumulated depreciation and amortization	(811,474		)	(837,122		)
	$	361,547		$	398,466

Depreciation expense for fiscal years 2017, 2016 and 2015 was $32,131, $33,186 and $33,168, respectively. Landfill amortization expense for fiscal years 2017, 2016 and 2015 was $27,910, $26,529 and $26,969, respectively. Depletion expense on landfill operating lease contracts for fiscal years 2017, 2016 and 2015 was $9,646, $9,295 and $9,428, respectively, and was recorded in cost of operations.