INCOME TAXES (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Workers compensation and other claims related accruals	$ 15,316	$ 15,904
Provision for doubtful accounts	12,654	8,921
Closure, post-closure and remedial liabilities	37,407	43,640
Accrued expenses	12,455	13,451
Accrued compensation	5,425	12,094
Net operating loss carryforwards	41,191	46,740
Tax credit carryforwards	25,040	29,347
Uncertain tax positions accrued interest and federal benefit	1,219	1,953
Stock-based compensation	615	489
Other	7,421	3,622
Total deferred tax assets	158,743	176,161
Deferred tax liabilities:
Property, plant and equipment	(221,969)	(232,106)
Permits and other intangible assets	(159,698)	(155,326)
Total deferred tax liabilities	(381,667)	(387,432)
Total net deferred tax liability before valuation allowance	(222,924)	(211,271)
Less valuation allowance	(30,916)	(29,061)
Net deferred tax liabilities	(253,840)	$ (240,332)
State and local operating loss carryforwards	63,100
Domestic operating loss carryforwards	72,000
Foreign operating loss carryforwards	49,700
Foreign tax credit carryforwards	$ 25,000