SEGMENT INFORMATION (Details 1) - USD ($) $ in Millions	3 Months Ended	48 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020
Sales [Abstract]
Sales	$ 1,425.1	$ 1,553.4
Income (loss) before taxes:
Income (loss) before taxes	(105.9)	53.1
Corporate/Other:
Environmental expense	2.6	1.8
Restructuring charges	(1.7)	(4.0)	$ (242.0)
Other operating income	0.0	0.1
Interest expense	(63.1)	(57.4)
Interest income	0.1	0.2
Non-operating pension income	4.6	3.9
Other income	0.0	11.2
Chlor Alkali Products and Vinyls
Sales [Abstract]
Sales	759.9	872.2
Income (loss) before taxes:
Income (loss) before taxes	(34.3)	120.4
Epoxy
Sales [Abstract]
Sales	477.2	524.0
Income (loss) before taxes:
Income (loss) before taxes	11.7	10.5
Winchester
Sales [Abstract]
Sales	188.0	157.2
Income (loss) before taxes:
Income (loss) before taxes	10.5	9.1
Corporate/Other
Corporate/Other:
Environmental expense	2.6	1.8
Other corporate and unallocated costs	(31.1)	(39.1)
Restructuring charges	$ (1.7)	$ (4.0)

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