COMMITMENTS AND CONTINGENCIES (Self Insurance Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Product Liability Contingency [Line Items]
Retention for environmental impairment	$ 1,000
Self-insurance liabilities	$ 59,400	$ 53,900
Weighted average risk free discount rate for self insurance liabilities	1.52%	2.96%
Self Insurance Losses Expected [Abstract]
2020	$ 20,838
2021	12,675
2022	8,951
2023	6,097
2024	4,743
Thereafter	7,659
Undiscounted self-insurance liabilities	60,963
Less: Discount	1,570
Total self-insurance liabilities (included in accrued expenses)	59,393
Minimum
Product Liability Contingency [Line Items]
Deductible medical insurance policy	800
Safety-Kleen
Product Liability Contingency [Line Items]
Deductible per occurrence for workers compensation	1,000
Deductible per occurrence for general liability	2,000
Deductible per occurrence for vehicle liability	$ 2,000