COMMITMENTS AND CONTINGENCIES (Details)	1 Months Ended	3 Months Ended				12 Months Ended					3 Months Ended	12 Months Ended	3 Months Ended
	Oct. 31, 2010 customer	Mar. 31, 2015 USD ($) claims Proceedings	Dec. 31, 2014 USD ($)	Mar. 31, 2015 Legal and Administrative Proceedings USD ($)	Dec. 31, 2014 Legal and Administrative Proceedings USD ($)	Dec. 31, 2012 Ville Mercier CAD	Dec. 31, 1999 Ville Mercier Municipalities	Dec. 31, 1968 Ville Mercier Permits	Mar. 31, 2015 Ville Mercier USD ($)	Dec. 31, 2014 Ville Mercier USD ($)	Mar. 31, 2015 Superfund Proceedings sites facilties	Dec. 31, 2002 Wichita Property acre	Mar. 31, 2015 Certain Other Third Party Sites sites	Mar. 31, 2015 Safety-Kleen sites	Mar. 31, 2015 Federal and State Enforcement Actions USD ($) Proceedings	Dec. 31, 2014 Federal and State Enforcement Actions USD ($) Proceedings
Contingencies [Line Items]
Recorded reserves for actual or probable liabilities		$ 29,800,000	$ 33,600,000	$ 24,100,000	$ 27,700,000										$ 5,700,000	$ 5,900,000
Possible increase in legal and administrative proceedings				2,500,000	2,900,000
Number of permits issued by government, for dumping organic liquid								2
Number of neighboring municipalities filing separate legal proceedings against the Mercier Subsidiary and the Government of Quebec							3
General damages sought						2,900,000
Punitive damages sought						10,000,000
Accrued remedial liabilities		149,745,000	155,121,000						11,600,000	12,700,000
Number of pending personal injury claims allegedly resulting from the used of Safety-Kleen's products		54													3	4
Number of product liability claims settled or dismissed		11
Number of customers filing a complaint	2
Number of sites owned by third party excluded from cleanup or related liabilities											127
Number of sites owned by the entity subject to proceedings under federal or state superfund laws											2
Notices received from owners of third party sites seeking indemnification from the company											125
Number of sites for which environmental remediation expense is settled											29
Third party sites requiring expenditure on remediation											22
Number of sites not currently requiring expenditures on remediation											74
Minimum potential liability															$ 100,000	$ 100,000
Number of sites which potential liability could exceed $100,000											12
State-designated superfund site acquired, total acres												1,400
Indemnification agreement with third party sites													11
Notices received from owners of third party sites seeking indemnification from the company											5			16