SEGMENT INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended		56 Months Ended
	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Mar. 31, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015
Segment Reporting Information [Line Items]
Total sales	$ 535.4		$ 570.4		$ 1,053.4	$ 1,147.8
Income before taxes [Abstract]
Income from continuing operations before taxes	63.7		54.8		83.3	103.0
Restructuring charges	(0.7)	$ (1.2)	(2.3)	$ (1.0)	(1.9)	(3.3)	$ (76.5)
Acquisition-related costs	10.5		0.2		20.9	0.4
Other operating income	42.4		0.9		42.2	0.8
Interest expense	(18.2)		(9.6)		(25.3)	(19.3)
Interest income	0.3		0.4		0.6	0.7
Chlor Alkali Products
Segment Reporting Information [Line Items]
Total sales	294.7		338.5		587.4	666.8
Income before taxes [Abstract]
Income from continuing operations before taxes	25.0		40.8		48.1	75.1
Chemical Distribution
Segment Reporting Information [Line Items]
Total sales	70.3		75.6		140.1	144.8
Income before taxes [Abstract]
Income from continuing operations before taxes	2.4		0.0		3.4	(0.8)
Winchester
Segment Reporting Information [Line Items]
Total sales	194.2		181.0		372.9	381.6
Income before taxes [Abstract]
Income from continuing operations before taxes	33.9		33.1		63.7	71.4
Intersegment Elimination
Segment Reporting Information [Line Items]
Total sales	(23.8)		(24.7)		(47.0)	(45.4)
Corporate/Other
Income before taxes [Abstract]
Pension income	7.4		7.5		14.5	15.4
Environmental expense	(5.1)		(1.2)		(5.8)	(4.7)
Other corporate and unallocated costs	(13.2)		(14.6)		(35.3)	(31.9)
Restructuring charges	(0.7)		(2.3)		(1.9)	(3.3)
Acquisition-related costs	$ 10.5		$ 0.2		$ 20.9	$ 0.4