SEGMENT INFORMATION (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended						9 Months Ended		35 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013
Segment Reporting Information [Line Items]
Segment Reporting Information, Intersegment Revenue	$ 18.5			$ 4.8			$ 62.1	$ 4.8
Synergies Transferred Between Segments	2.9						9.1
Total sales	670.7			581.2			1,952.9	1,597.1
Income before taxes [Abstract]
Income before taxes	93.0			46.7			219.5	170.5
Environmental expense	(0.7)			(3.6)			(4.9)	(6.7)
Restructuring charges	(1.6)	(0.2)	(2.3)	(2.3)	(1.8)	(1.9)	(4.1)	(6.0)	(57.5)
Acquisition costs	0			8.3			0	8.3
Other operating (expense) income	(0.4)			1.1			1.3	1.5
Interest expense	(9.9)			(6.0)			(28.7)	(18.3)
Interest income	0.1			0.2			0.3	0.7
Other expense	(1.9)			(2.2)			(6.3)	(6.9)
Chlor Alkali Products [Member]
Segment Reporting Information [Line Items]
Total sales	374.2			369.6			1,090.1	1,092.5
Income before taxes [Abstract]
Income before taxes	64.4			59.5			173.1	208.9
Chemical Distribution [Member]
Segment Reporting Information [Line Items]
Total sales	101.9			47.6			325.7	47.6
Income before taxes [Abstract]
Income before taxes	3.4			1.9			9.7	1.9
Winchester [Member]
Segment Reporting Information [Line Items]
Total sales	213.1			168.8			599.2	461.8
Income before taxes [Abstract]
Income before taxes	40.7			16.0			109.1	38.7
Corporate/Other [Member]
Income before taxes [Abstract]
Pension income	7.3			7.2			20.0	20.5
Environmental expense	(0.7)			(3.6)			(4.9)	(6.7)
Other corporate and unallocated costs	(8.4)			(16.8)			(50.0)	(55.5)
Restructuring charges	(1.6)			(2.3)			(4.1)	(6.0)
Acquisition costs	$ 0			$ (8.3)			$ 0	$ (8.3)