GUARANTOR AND NON-GUARANTOR SUBSIDIARIES FINANCIAL INFORMATION (Details 2) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
ASSETS
Cash and cash equivalents	$ 296,758	$ 260,723	$ 377,576	$ 302,210
Intercompany receivables	0	0
Other current assets	568,750	631,145
Property, plant and equipment, net	955,040	903,947
Investments in subsidiaries	0	0
Intercompany debt receivable	0	0
Other long-term assets	301,666	289,988
Total assets	2,122,214	2,085,803
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	361,321	381,742
Intercompany payables	0	0
Closure, post-closure and remedial liabilities, net	147,703	155,142
Long-term obligations	523,481	524,203
Capital lease obligations, net	4,482	6,375
Intercompany debt payable	0	0
Other long-term liabilities	124,327	117,354
Total liabilities	1,161,314	1,184,816
Stockholders' equity	960,900	900,987
Total liabilities and stockholders' equity	2,122,214	2,085,803
Clean Harbors, Inc.
ASSETS
Cash and cash equivalents	94,960	91,581	196,896	100,476
Intercompany receivables	324,405	319,444
Other current assets	26,294	43,687
Property, plant and equipment, net	0	0
Investments in subsidiaries	1,138,424	1,064,966
Intercompany debt receivable	0	0
Other long-term assets	12,328	13,228
Total assets	1,596,411	1,532,906
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	18,580	15,612
Intercompany payables	0	0
Closure, post-closure and remedial liabilities, net	0	0
Long-term obligations	523,481	524,203
Capital lease obligations, net	0	0
Intercompany debt payable	3,701	3,701
Other long-term liabilities	89,749	88,403
Total liabilities	635,511	631,919
Stockholders' equity	960,900	900,987
Total liabilities and stockholders' equity	1,596,411	1,532,906
U.S. Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	138,482	128,071	118,563	124,582
Intercompany receivables	0	0
Other current assets	332,701	324,607
Property, plant and equipment, net	417,583	392,566
Investments in subsidiaries	473,506	421,648
Intercompany debt receivable	472,279	472,929
Other long-term assets	111,993	111,104
Total assets	1,946,544	1,850,925
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	227,821	220,968
Intercompany payables	447,023	446,267
Closure, post-closure and remedial liabilities, net	126,245	133,773
Long-term obligations	0	0
Capital lease obligations, net	357	475
Intercompany debt payable	0	0
Other long-term liabilities	7,727	7,588
Total liabilities	809,173	809,071
Stockholders' equity	1,137,371	1,041,854
Total liabilities and stockholders' equity	1,946,544	1,850,925
Foreign Non-Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	63,316	41,071	62,117	77,152
Intercompany receivables	122,618	126,823
Other current assets	209,755	262,851
Property, plant and equipment, net	537,457	511,381
Investments in subsidiaries	91,751	91,654
Intercompany debt receivable	3,701	3,701
Other long-term assets	177,345	165,656
Total assets	1,205,943	1,203,137
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	114,920	145,162
Intercompany payables	0	0
Closure, post-closure and remedial liabilities, net	21,458	21,369
Long-term obligations	0	0
Capital lease obligations, net	4,125	5,900
Intercompany debt payable	472,279	472,929
Other long-term liabilities	26,851	21,363
Total liabilities	639,633	666,723
Stockholders' equity	566,310	536,414
Total liabilities and stockholders' equity	1,205,943	1,203,137
Consolidating Adjustments
ASSETS
Cash and cash equivalents	0	0
Intercompany receivables	(447,023)	(446,267)
Other current assets	0	0
Property, plant and equipment, net	0	0
Investments in subsidiaries	(1,703,681)	(1,578,268)
Intercompany debt receivable	(475,980)	(476,630)
Other long-term assets	0	0
Total assets	(2,626,684)	(2,501,165)
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities	0	0
Intercompany payables	(447,023)	(446,267)
Closure, post-closure and remedial liabilities, net	0	0
Long-term obligations	0	0
Capital lease obligations, net	0	0
Intercompany debt payable	(475,980)	(476,630)
Other long-term liabilities	0	0
Total liabilities	(923,003)	(922,897)
Stockholders' equity	(1,703,681)	(1,578,268)
Total liabilities and stockholders' equity	$ (2,626,684)	$ (2,501,165)