GOODWILL AND OTHER INTANGIBLE ASSETS (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2013 Chlorovinyls	Mar. 31, 2013 Building Products	Dec. 31, 2012 Building Products
Changes made to goodwill by reportable segment
Gross goodwill at the beginning of the period	$ 404.9	$ 245.4	$ 159.5	$ 159.5
Accumulated impairment losses at the beginning of the period	(187.7)	(55.5)	(132.2)	(132.2)
Net goodwill at the beginning of the period	217.2	189.9	27.3	27.3
Preliminary addition from the Transactions	1,454.3	1,454.3
Foreign currency translation adjustment	(4.3)	(4.3)
Gross goodwill at the end of the period	1,854.9	1,695.4	159.5	159.5
Accumulated impairment losses at the end of the period	(187.7)	(55.5)	(132.2)	(132.2)
Net goodwill at the end of the period	$ 1,667.2	$ 1,639.9	$ 27.3	$ 27.3