SEGMENT INFORMATION (Details 1) - USD ($) $ in Millions	3 Months Ended	52 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019
Sales [Abstract]
Sales	$ 1,553.4	$ 1,710.3
Income (loss) before taxes:
Income (loss) before taxes	53.1	27.5
Corporate/Other:
Environmental expense	1.8	2.3
Restructuring charges	(4.0)	(4.0)	$ (186.0)
Acquisition-related costs	0.0	(0.3)
Other operating income	0.1	8.1
Interest expense	(57.4)	(63.7)
Interest income	0.2	0.4
Non-operating pension income	3.9	5.4
Other income	11.2	0.0
Gain in Other Operating (Expense) Income due to Insurance Recoveries		8.0
Chlor Alkali Products and Vinyls
Sales [Abstract]
Sales	872.2	936.1
Income (loss) before taxes:
Income (loss) before taxes	120.4	130.5
Epoxy
Sales [Abstract]
Sales	524.0	603.3
Income (loss) before taxes:
Income (loss) before taxes	10.5	(22.1)
Winchester
Sales [Abstract]
Sales	157.2	170.9
Income (loss) before taxes:
Income (loss) before taxes	9.1	12.0
Corporate/Other [Member]
Corporate/Other:
Environmental expense	1.8	2.3
Other corporate and unallocated costs	(39.1)	(36.5)
Restructuring charges	(4.0)	(4.0)
Acquisition-related costs	$ 0.0	$ (0.3)

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The gain recorded in other operating income due to insurance recoveries for property damage and business interruption.

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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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