RESTRUCTURING CHARGE (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended		41 Months Ended				3 Months Ended		41 Months Ended	3 Months Ended		41 Months Ended		3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 09, 2010 T	Mar. 31, 2014 Chlor Alkali Products Segment [Member]	Mar. 31, 2013 Chlor Alkali Products Segment [Member]	Mar. 31, 2014 Chlor Alkali Products Segment [Member]	Mar. 31, 2014 Winchester Segment [Member]	Mar. 31, 2013 Winchester Segment [Member]	Mar. 31, 2014 Winchester Segment [Member]	Dec. 31, 2011 Winchester Segment [Member]	Mar. 31, 2014 Winchester Segment [Member] Minimum [Member]	Mar. 31, 2014 Winchester Segment [Member] Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Previous mercury cell capacity tonnage at Charleston, TN facility (in tons)						260,000
Membrane capacity tonnage capability at Charleston, TN facility (in tons)						200,000
Percentage reduction of electricity usage per ECU produced (in hundredths)	25.00%		25.00%
Product Segment Production Capacity Decrease						160,000
Restructuring charges	$ 1.0	$ 2.3	$ 59.9				$ 0.6	$ 1.5	$ 37.4	$ 0.4	$ 0.8	$ 22.5
Restructuring And Related Cost Expected Cost							2			5
Forecast annual reduction of Winchester's annual operating costs														35	40
Estimated five-year project cost for Winchester relocation										110		110
Estimated capital spending for Winchester relocation										80		80
Government Grants for Facility Relocation Capital Spending													31
Inception to date Amounts Utilized (cash)			21.8
Inception to date Amounts Utilized (non-cash)			28.3
Accrued restructuring costs	$ 9.8	$ 13.7	$ 9.8	$ 10.2	$ 13.9