GUARANTOR AND NON-GUARANTOR SUBSIDIARIES (Income Statement) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues
Service revenues									$ 2,398,650	$ 2,280,809	$ 2,744,272
Product revenues									546,328	474,417	530,865
Total revenues	$ 747,403	$ 755,846	$ 752,788	$ 688,941	$ 692,113	$ 729,520	$ 697,510	$ 636,083	2,944,978	2,755,226	3,275,137
Cost of revenues (exclusive of items shown separately below)
Service cost of revenues									1,641,798	1,543,210	1,898,907
Product cost of revenues									420,875	389,647	457,899
Total cost of revenues	526,690	519,595	519,803	496,585	496,661	491,915	480,002	464,279	2,062,673	1,932,857	2,356,806
Selling, general and administrative expenses									456,648	422,015	414,164
Accretion of environmental liabilities									9,460	10,177	10,402
Depreciation and amortization									288,422	287,002	274,194
Goodwill impairment charges						34,000			0	34,013	31,992
Income (loss) from operations	27,935	47,663	46,744	5,433	21,943	16,802	34,504	(4,087)	127,775	69,162	187,579
Other (expense) income, net	(3,305)	(432)	(833)	(1,549)	6,932	(198)	(189)	(350)	(6,119)	6,195	(1,380)
Loss on early extinguishment of debt		(1,900)	(6,000)						(7,891)	0	0
Gain on sale of businesses			31,700			16,400			30,732	16,884	0
Interest (expense) income, net									(85,808)	(83,525)	(76,553)
Equity in earnings of subsidiaries, net of tax									0	0	0
Intercompany interest income (expense)									0	0	0
Income (loss) before (benefit) provision for income taxes									58,689	8,716	109,646
(Benefit) provision for income taxes									(42,050)	48,589	65,544
Net income (loss)	$ 84,194	$ 12,058	$ 25,880	$ (21,393)	$ (12,713)	$ (10,255)	$ 3,966	$ (20,871)	100,739	(39,873)	44,102
Other comprehensive income									41,919	40,566	(144,050)
Comprehensive income (loss)									142,658	693	(99,948)
Reportable Legal Entities | Clean Harbors, Inc.
Revenues
Service revenues									0	0	0
Product revenues									0	0	0
Total revenues									0	0	0
Cost of revenues (exclusive of items shown separately below)
Service cost of revenues									0	0	5
Product cost of revenues									0	0	0
Total cost of revenues									0	0	5
Selling, general and administrative expenses									0	85	101
Accretion of environmental liabilities									0	0	0
Depreciation and amortization									0	0	0
Goodwill impairment charges										0	0
Income (loss) from operations									0	(85)	(106)
Other (expense) income, net									(222)	0	0
Loss on early extinguishment of debt									(7,891)
Gain on sale of businesses									0	0
Interest (expense) income, net									(87,113)	(88,984)	(78,621)
Equity in earnings of subsidiaries, net of tax									157,963	13,568	91,339
Intercompany interest income (expense)									0	0	0
Income (loss) before (benefit) provision for income taxes									62,737	(75,501)	12,612
(Benefit) provision for income taxes									(38,002)	(35,628)	(31,490)
Net income (loss)									100,739	(39,873)	44,102
Other comprehensive income									41,919	40,566	(144,050)
Comprehensive income (loss)									142,658	693	(99,948)
Reportable Legal Entities | Guarantor Subsidiaries
Revenues
Service revenues									1,870,256	1,747,985	2,111,086
Product revenues									492,036	410,868	458,314
Total revenues									2,362,292	2,158,853	2,569,400
Cost of revenues (exclusive of items shown separately below)
Service cost of revenues									1,224,326	1,116,132	1,415,435
Product cost of revenues									386,455	349,069	410,128
Total cost of revenues									1,610,781	1,465,201	1,825,563
Selling, general and administrative expenses									373,050	341,963	329,069
Accretion of environmental liabilities									8,479	9,261	9,209
Depreciation and amortization									205,034	201,153	184,017
Goodwill impairment charges										0	4,164
Income (loss) from operations									164,948	141,275	217,378
Other (expense) income, net									(5,156)	7,713	491
Loss on early extinguishment of debt									0
Gain on sale of businesses									30,732	1,704
Interest (expense) income, net									1,523	5,391	1,860
Equity in earnings of subsidiaries, net of tax									(48,683)	(80,244)	(47,141)
Intercompany interest income (expense)									5,288	19,855	23,156
Income (loss) before (benefit) provision for income taxes									148,652	95,694	195,744
(Benefit) provision for income taxes									(10,117)	82,643	104,405
Net income (loss)									158,769	13,051	91,339
Other comprehensive income									41,919	40,566	(144,050)
Comprehensive income (loss)									200,688	53,617	(52,711)
Reportable Legal Entities | Non-Guarantor Subsidiaries
Revenues
Service revenues									582,042	582,075	692,216
Product revenues									66,511	73,793	83,970
Total revenues									648,553	655,868	776,186
Cost of revenues (exclusive of items shown separately below)
Service cost of revenues									471,120	476,329	542,497
Product cost of revenues									46,639	50,822	59,190
Total cost of revenues									517,759	527,151	601,687
Selling, general and administrative expenses									83,598	79,967	84,994
Accretion of environmental liabilities									981	916	1,193
Depreciation and amortization									83,388	85,849	90,177
Goodwill impairment charges										34,013	27,828
Income (loss) from operations									(37,173)	(72,028)	(29,693)
Other (expense) income, net									(741)	(1,518)	(1,871)
Loss on early extinguishment of debt									0
Gain on sale of businesses									0	15,180
Interest (expense) income, net									(218)	68	208
Equity in earnings of subsidiaries, net of tax									0	0	0
Intercompany interest income (expense)									(5,288)	(19,855)	(23,156)
Income (loss) before (benefit) provision for income taxes									(43,420)	(78,153)	(54,512)
(Benefit) provision for income taxes									6,069	1,574	(7,371)
Net income (loss)									(49,489)	(79,727)	(47,141)
Other comprehensive income									38,131	15,291	(93,983)
Comprehensive income (loss)									(11,358)	(64,436)	(141,124)
Consolidating Adjustments
Revenues
Service revenues									(53,648)	(49,251)	(59,030)
Product revenues									(12,219)	(10,244)	(11,419)
Total revenues									(65,867)	(59,495)	(70,449)
Cost of revenues (exclusive of items shown separately below)
Service cost of revenues									(53,648)	(49,251)	(59,030)
Product cost of revenues									(12,219)	(10,244)	(11,419)
Total cost of revenues									(65,867)	(59,495)	(70,449)
Selling, general and administrative expenses									0	0	0
Accretion of environmental liabilities									0	0	0
Depreciation and amortization									0	0	0
Goodwill impairment charges										0	0
Income (loss) from operations									0	0	0
Other (expense) income, net									0	0	0
Loss on early extinguishment of debt									0
Gain on sale of businesses									0	0
Interest (expense) income, net									0	0	0
Equity in earnings of subsidiaries, net of tax									(109,280)	66,676	(44,198)
Intercompany interest income (expense)									0	0	0
Income (loss) before (benefit) provision for income taxes									(109,280)	66,676	(44,198)
(Benefit) provision for income taxes									0	0	0
Net income (loss)									(109,280)	66,676	(44,198)
Other comprehensive income									(80,050)	(55,857)	238,033
Comprehensive income (loss)									$ (189,330)	$ 10,819	$ 193,835