Estimated capital spending for facility relocation.

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- Definition

Estimated project cost for plant relocation.

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- Definition

Forecast production capacity at a facility.

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- Definition

Percentage Of Capital Spending Offset Provided By State Government.

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No definition available.

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- Definition

Percentage reduction or increase of electricity used per product unit produced.

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No definition available.

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- Definition

Previous production capacity for an item at a facility.

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- Definition

Tonnage capacity reduction in a product segment.

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- Definition

The quantified amount of the future effect on earnings.

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Amount expected to be charged against earnings in the current and future periods for the specified restructuring cost.

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-Name Statement of Financial Accounting Standard (FAS)

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Amount charged against earnings in the period for incurred and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding asset retirement obligations.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of cash paid in the period to fully or partially settle a specified, previously accrued type of restructuring cost.

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Amount of consideration other than cash paid in the period to fully or partially settle a specified, previously accrued type of restructuring cost.

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RESTRUCTURING CHARGE (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended		32 Months Ended
	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2012	Mar. 31, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 09, 2010 T
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%		25.00%
Product Segment Production Capacity Decrease										160,000
Forecast annual reduction of Winchester's annual operating costs					$ 30
Estimated five-year project cost for Winchester relocation	110				110		110
Estimated capital spending for Winchester relocation	80				80		80
Percentage of capital spending offset provided by State of Mississippi tax incentives (in hundredths)	40.00%				40.00%		40.00%
Restructuring charges	0.2	2.3	1.8	1.9	2.5	3.7	55.9
Inception to date Amounts Utilized (cash)							15.6
Inception to date Amounts Utilized (non-cash)							28.3
Accrued restructuring costs	12.0		12.7		12.0	12.7	12.0	13.9	12.1
Chlor Alkali Products Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	(0.1)		0.2		1.4	0.5	34.5
Restructuring And Related Cost Expected Cost					5
Winchester Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.3		1.6		1.1	3.2	21.4
Restructuring And Related Cost Expected Cost					$ 7