RESTRUCTURING CHARGE (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended						9 Months Ended		23 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 2.3	$ 1.8	$ 1.9	$ 4.1	$ 2.4	$ 0.1	$ 6.0	$ 6.6	$ 50.9
Write-off of equipment and facility [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									17.5
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1.3	1.0	0.9	2.7	0.9	0.1			15.6
Facility Exit Costs (asset retirement obligations [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.5	0.1	0.2	0.4	0.1	0			8.5
Pension and other postretirement benefits curtailment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0	0	0	0	1.1	0			4.1
Employee Relocation Cost [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.5	0.7	0.8	1.0	0.3	0			4.2
Lease and Other Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0	0	0	0	0	0			1.0
Winchester Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1.8			2.1			5.0	4.3	19.1
Winchester Segment [Member] | Write-off of equipment and facility [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									0
Winchester Segment [Member] | Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									10.1
Winchester Segment [Member] | Facility Exit Costs (asset retirement obligations [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									0.8
Winchester Segment [Member] | Pension and other postretirement benefits curtailment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									4.1
Winchester Segment [Member] | Employee Relocation Cost [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									4.1
Winchester Segment [Member] | Lease and Other Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									0
Chlor Alkali Products Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.5			2.0			1.0	2.3	31.8
Chlor Alkali Products Segment [Member] | Write-off of equipment and facility [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									17.5
Chlor Alkali Products Segment [Member] | Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									5.5
Chlor Alkali Products Segment [Member] | Facility Exit Costs (asset retirement obligations [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									7.7
Chlor Alkali Products Segment [Member] | Pension and other postretirement benefits curtailment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									0
Chlor Alkali Products Segment [Member] | Employee Relocation Cost [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									0.1
Chlor Alkali Products Segment [Member] | Lease and Other Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges									$ 1.0