GUARANTOR AND NON-GUARANTOR SUBSIDIARIES FINANCIAL INFORMATION (Condensed Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
ASSETS
Cash and cash equivalents	$ 257,857	$ 184,708	$ 179,191	$ 246,879
Intercompany receivables	0	0
Accounts receivable, net	512,376	496,004
Other current assets	279,698	240,484
Property, plant and equipment, net	1,648,571	1,532,467
Investments in subsidiaries	0	0
Intercompany debt receivable	0	0
Goodwill	470,633	453,105
Permits and other intangibles, net	507,337	506,818
Other long-term assets	36,141	17,842
Total assets	3,712,613	3,431,428
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	539,096	517,120
Intercompany payables	0	0
Closure, post-closure and remedial liabilities, net	171,431	167,846
Long-term obligations	1,632,577	1,382,543
Intercompany debt payable	0	0
Other long-term liabilities	268,564	267,637
Total liabilities	2,611,668	2,335,146
Stockholders’ equity	1,100,945	1,096,282
Total liabilities and stockholders’ equity	3,712,613	3,431,428
Reportable Legal Entities | Clean Harbors, Inc.
ASSETS
Cash and cash equivalents	51,334	11,017	11,008	1,006
Intercompany receivables	190,728	164,709
Accounts receivable, net	0	0
Other current assets	2,537	0
Property, plant and equipment, net	0	0
Investments in subsidiaries	2,813,894	2,547,307
Intercompany debt receivable	0	0
Goodwill	0	0
Permits and other intangibles, net	0	0
Other long-term assets	1,197	1,068
Total assets	3,059,690	2,724,101
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	22,619	20,813
Intercompany payables	299,848	220,762
Closure, post-closure and remedial liabilities, net	0	0
Long-term obligations	1,632,577	1,382,543
Intercompany debt payable	3,701	3,701
Other long-term liabilities	0	0
Total liabilities	1,958,745	1,627,819
Stockholders’ equity	1,100,945	1,096,282
Total liabilities and stockholders’ equity	3,059,690	2,724,101
Reportable Legal Entities | U.S. Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	170,183	83,479	66,074	154,147
Intercompany receivables	300,656	213,243
Accounts receivable, net	418,170	404,580
Other current assets	207,488	179,969
Property, plant and equipment, net	1,217,704	1,082,466
Investments in subsidiaries	488,437	522,067
Intercompany debt receivable	212,171	260,957
Goodwill	417,992	367,306
Permits and other intangibles, net	439,543	435,080
Other long-term assets	9,552	10,274
Total assets	3,881,896	3,559,421
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	438,298	424,588
Intercompany payables	224,593	195,287
Closure, post-closure and remedial liabilities, net	155,710	153,190
Long-term obligations	0	0
Intercompany debt payable	0	0
Other long-term liabilities	249,401	239,049
Total liabilities	1,068,002	1,012,114
Stockholders’ equity	2,813,894	2,547,307
Total liabilities and stockholders’ equity	3,881,896	3,559,421
Reportable Legal Entities | Foreign Non-Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	36,340	90,212	102,109	91,726
Intercompany receivables	34,665	39,804
Accounts receivable, net	94,206	91,424
Other current assets	69,673	60,515
Property, plant and equipment, net	430,867	450,001
Investments in subsidiaries	0	0
Intercompany debt receivable	3,701	3,701
Goodwill	52,641	85,799
Permits and other intangibles, net	67,794	71,738
Other long-term assets	25,392	6,500
Total assets	815,279	899,694
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	78,179	71,719
Intercompany payables	1,608	1,707
Closure, post-closure and remedial liabilities, net	15,721	14,656
Long-term obligations	0	0
Intercompany debt payable	212,171	260,957
Other long-term liabilities	19,163	28,588
Total liabilities	326,842	377,627
Stockholders’ equity	488,437	522,067
Total liabilities and stockholders’ equity	815,279	899,694
Consolidating Adjustments
ASSETS
Cash and cash equivalents	0	0	$ 0	$ 0
Intercompany receivables	(526,049)	(417,756)
Accounts receivable, net	0	0
Other current assets	0	0
Property, plant and equipment, net	0	0
Investments in subsidiaries	(3,302,331)	(3,069,374)
Intercompany debt receivable	(215,872)	(264,658)
Goodwill	0	0
Permits and other intangibles, net	0	0
Other long-term assets	0	0
Total assets	(4,044,252)	(3,751,788)
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	0	0
Intercompany payables	(526,049)	(417,756)
Closure, post-closure and remedial liabilities, net	0	0
Long-term obligations	0	0
Intercompany debt payable	(215,872)	(264,658)
Other long-term liabilities	0	0
Total liabilities	(741,921)	(682,414)
Stockholders’ equity	(3,302,331)	(3,069,374)
Total liabilities and stockholders’ equity	$ (4,044,252)	$ (3,751,788)