GUARANTOR AND NON-GUARANTOR SUBSIDIARIES FINANCIAL INFORMATION (Consolidating Statement of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues:
Service revenues	$ 619,719	$ 560,214
Product revenues	130,059	128,727
Total revenues	749,778	688,941
Cost of revenues: (exclusive of items shown separately below)
Service cost of revenues	447,649	391,087
Product cost of revenues	98,776	105,498
Total cost of revenues	546,425	496,585
Selling, general and administrative expenses	115,088	112,221
Accretion of environmental liabilities	2,430	2,290
Depreciation and amortization	74,844	72,412
Income from operations	10,991	5,433
Other expense, net	(299)	(1,549)
Interest (expense) income, net	(20,270)	(22,576)
Equity in earnings of subsidiaries, net of taxes	0	0
Intercompany interest income (expense)	0	0
(Loss) income before (benefit) provision for income taxes	(9,578)	(18,692)
(Benefit) provision for income taxes	3,053	2,701
Net loss	(12,631)	(21,393)
Other comprehensive loss	(16,746)	6,051
Comprehensive loss	(29,377)	(15,342)
Reportable Legal Entities | Clean Harbors, Inc.
Revenues:
Service revenues	0	0
Product revenues	0	0
Total revenues	0	0
Cost of revenues: (exclusive of items shown separately below)
Service cost of revenues	0	0
Product cost of revenues	0	0
Total cost of revenues	0	0
Selling, general and administrative expenses	35	24
Accretion of environmental liabilities	0	0
Depreciation and amortization	0	0
Income from operations	(35)	(24)
Other expense, net	0	(146)
Interest (expense) income, net	(20,999)	(22,659)
Equity in earnings of subsidiaries, net of taxes	2,514	(7,637)
Intercompany interest income (expense)	0	0
(Loss) income before (benefit) provision for income taxes	(18,520)	(30,466)
(Benefit) provision for income taxes	(5,889)	(9,073)
Net loss	(12,631)	(21,393)
Other comprehensive loss	(16,746)	6,051
Comprehensive loss	(29,377)	(15,342)
Reportable Legal Entities | Guarantor Subsidiaries
Revenues:
Service revenues	481,483	443,305
Product revenues	121,582	116,650
Total revenues	603,065	559,955
Cost of revenues: (exclusive of items shown separately below)
Service cost of revenues	328,180	294,145
Product cost of revenues	95,038	96,505
Total cost of revenues	423,218	390,650
Selling, general and administrative expenses	93,843	92,171
Accretion of environmental liabilities	2,176	2,055
Depreciation and amortization	53,704	51,900
Income from operations	30,124	23,179
Other expense, net	(85)	(1,389)
Interest (expense) income, net	505	119
Equity in earnings of subsidiaries, net of taxes	(20,062)	(21,824)
Intercompany interest income (expense)	1,361	1,297
(Loss) income before (benefit) provision for income taxes	11,843	1,382
(Benefit) provision for income taxes	9,101	9,637
Net loss	2,742	(8,255)
Other comprehensive loss	(16,746)	6,051
Comprehensive loss	(14,004)	(2,204)
Reportable Legal Entities | Non-Guarantor Subsidiaries
Revenues:
Service revenues	152,401	131,071
Product revenues	11,450	15,331
Total revenues	163,851	146,402
Cost of revenues: (exclusive of items shown separately below)
Service cost of revenues	133,634	111,104
Product cost of revenues	6,711	12,247
Total cost of revenues	140,345	123,351
Selling, general and administrative expenses	21,210	20,026
Accretion of environmental liabilities	254	235
Depreciation and amortization	21,140	20,512
Income from operations	(19,098)	(17,722)
Other expense, net	(214)	(14)
Interest (expense) income, net	224	(36)
Equity in earnings of subsidiaries, net of taxes	0	0
Intercompany interest income (expense)	(1,361)	(1,297)
(Loss) income before (benefit) provision for income taxes	(20,449)	(19,069)
(Benefit) provision for income taxes	(159)	2,137
Net loss	(20,290)	(21,206)
Other comprehensive loss	(14,007)	5,032
Comprehensive loss	(34,297)	(16,174)
Consolidating Adjustments
Revenues:
Service revenues	(14,165)	(14,162)
Product revenues	(2,973)	(3,254)
Total revenues	(17,138)	(17,416)
Cost of revenues: (exclusive of items shown separately below)
Service cost of revenues	(14,165)	(14,162)
Product cost of revenues	(2,973)	(3,254)
Total cost of revenues	(17,138)	(17,416)
Selling, general and administrative expenses	0	0
Accretion of environmental liabilities	0	0
Depreciation and amortization	0	0
Income from operations	0	0
Other expense, net	0	0
Interest (expense) income, net	0	0
Equity in earnings of subsidiaries, net of taxes	17,548	29,461
Intercompany interest income (expense)	0	0
(Loss) income before (benefit) provision for income taxes	17,548	29,461
(Benefit) provision for income taxes	0	0
Net loss	17,548	29,461
Other comprehensive loss	30,753	(11,083)
Comprehensive loss	$ 48,301	$ 18,378