SEGMENT INFORMATION (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 segment	Mar. 31, 2013
Segment information
Number of reportable segments	3
Segment information
Total net sales	$ 993.7	$ 1,061.2
Operating income (loss)	(0.4)	71.2
Interest expense, net	(18.3)	(18.3)
Loss on redemption and other debt costs		(78.5)
Gain on acquisition of controlling interest		23.5
Foreign exchange gain	0.4	0.1
Loss before income taxes	(18.3)	(2.0)
Operating segments
Segment information
Total net sales	993.7	1,061.2
Chlorovinyls
Segment information
Total net sales	682.2	614.5
Operating income (loss)	23.3	91.3
Chlorovinyls | Operating segments
Segment information
Total net sales	734.0	673.0
Chlorovinyls | Intersegment elimination
Segment information
Total net sales	51.8	58.5
Building Products
Segment information
Number of primary product groups	2
Segment information
Total net sales	154.7	162.2
Operating income (loss)	(10.8)	(13.8)
Building Products | Operating segments
Segment information
Total net sales	154.7	162.2
Aromatics
Segment information
Total net sales	156.8	284.5
Operating income (loss)	4.5	13.0
Aromatics | Operating segments
Segment information
Total net sales	156.8	284.5
Eliminations, Unallocated and Other
Segment information
Operating income (loss)	(17.4)	(19.3)
Eliminations, Unallocated and Other | Operating segments
Segment information
Total net sales	(51.8)	(58.5)
Eliminations, Unallocated and Other | Intersegment elimination
Segment information
Total net sales	$ (51.8)	$ (58.5)