GUARANTOR AND NON-GUARANTOR SUBSIDIARIES FINANCIAL INFORMATION (Condensed Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
ASSETS
Cash and cash equivalents	$ 352,923	$ 184,708	$ 173,621	$ 246,879
Intercompany receivables	0	0
Accounts receivable, net	503,749	496,004
Other current assets	262,462	240,484
Property, plant and equipment, net	1,594,987	1,532,467
Investments in subsidiaries	0	0
Intercompany debt receivable	0	0
Goodwill	461,491	453,105
Permits and other intangibles, net	492,224	506,818
Other long-term assets	24,545	17,842
Total assets	3,692,381	3,431,428
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	520,421	517,120
Intercompany payables	0	0
Closure, post-closure and remedial liabilities, net	165,434	167,846
Long-term obligations	1,631,881	1,382,543
Intercompany debt payable	0	0
Other long-term liabilities	258,302	267,637
Total liabilities	2,576,038	2,335,146
Stockholders’ equity	1,116,343	1,096,282
Total liabilities and stockholders’ equity	3,692,381	3,431,428
Reportable Legal Entities | Clean Harbors, Inc.
ASSETS
Cash and cash equivalents	51,291	11,017	4,208	1,006
Intercompany receivables	181,741	164,709
Accounts receivable, net	0	0
Other current assets	378	0
Property, plant and equipment, net	0	0
Investments in subsidiaries	2,833,394	2,547,307
Intercompany debt receivable	0	0
Goodwill	0	0
Permits and other intangibles, net	0	0
Other long-term assets	1,412	1,068
Total assets	3,068,216	2,724,101
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	21,852	20,813
Intercompany payables	294,439	220,762
Closure, post-closure and remedial liabilities, net	0	0
Long-term obligations	1,631,881	1,382,543
Intercompany debt payable	3,701	3,701
Other long-term liabilities	0	0
Total liabilities	1,951,873	1,627,819
Stockholders’ equity	1,116,343	1,096,282
Total liabilities and stockholders’ equity	3,068,216	2,724,101
Reportable Legal Entities | U.S. Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	224,493	83,479	80,577	154,147
Intercompany receivables	302,354	213,243
Accounts receivable, net	407,601	404,580
Other current assets	198,612	179,969
Property, plant and equipment, net	1,138,285	1,082,466
Investments in subsidiaries	514,708	522,067
Intercompany debt receivable	277,623	260,957
Goodwill	369,978	367,306
Permits and other intangibles, net	423,932	435,080
Other long-term assets	9,559	10,274
Total assets	3,867,145	3,559,421
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	427,367	424,588
Intercompany payables	217,430	195,287
Closure, post-closure and remedial liabilities, net	150,182	153,190
Long-term obligations	0	0
Intercompany debt payable	0	0
Other long-term liabilities	238,772	239,049
Total liabilities	1,033,751	1,012,114
Stockholders’ equity	2,833,394	2,547,307
Total liabilities and stockholders’ equity	3,867,145	3,559,421
Reportable Legal Entities | Foreign Non-Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	77,139	90,212	88,836	91,726
Intercompany receivables	30,741	39,804
Accounts receivable, net	96,148	91,424
Other current assets	63,472	60,515
Property, plant and equipment, net	456,702	450,001
Investments in subsidiaries	0	0
Intercompany debt receivable	3,701	3,701
Goodwill	91,513	85,799
Permits and other intangibles, net	68,292	71,738
Other long-term assets	13,574	6,500
Total assets	901,282	899,694
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	71,202	71,719
Intercompany payables	2,967	1,707
Closure, post-closure and remedial liabilities, net	15,252	14,656
Long-term obligations	0	0
Intercompany debt payable	277,623	260,957
Other long-term liabilities	19,530	28,588
Total liabilities	386,574	377,627
Stockholders’ equity	514,708	522,067
Total liabilities and stockholders’ equity	901,282	899,694
Consolidating Adjustments
ASSETS
Cash and cash equivalents	0	0	$ 0	$ 0
Intercompany receivables	(514,836)	(417,756)
Accounts receivable, net	0	0
Other current assets	0	0
Property, plant and equipment, net	0	0
Investments in subsidiaries	(3,348,102)	(3,069,374)
Intercompany debt receivable	(281,324)	(264,658)
Goodwill	0	0
Permits and other intangibles, net	0	0
Other long-term assets	0	0
Total assets	(4,144,262)	(3,751,788)
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	0	0
Intercompany payables	(514,836)	(417,756)
Closure, post-closure and remedial liabilities, net	0	0
Long-term obligations	0	0
Intercompany debt payable	(281,324)	(264,658)
Other long-term liabilities	0	0
Total liabilities	(796,160)	(682,414)
Stockholders’ equity	(3,348,102)	(3,069,374)
Total liabilities and stockholders’ equity	$ (4,144,262)	$ (3,751,788)