SEGMENT INFORMATION (Details 1) - USD ($) $ in Millions	12 Months Ended			69 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021
Sales [Abstract]
Sales	$ 8,910.6	$ 5,758.0	$ 6,110.0
Income (loss) before taxes [Abstract]
Income (loss) before taxes	(1,538.7)	1,020.0	36.9
Environmental expense	14.0	20.9	20.5
Restructuring charges	(27.9)	(9.0)	(76.5)	$ (271.3)
Goodwill, Impairment Loss	0.0	(699.8)	0.0
Other operating income	1.4	0.7	0.4
Interest expense	(348.0)	(292.7)	(243.2)
Interest income	0.2	0.5	1.0
Non-operating pension income	35.7	18.9	16.3
Other income	0.0	0.0	11.2
Depreciation and amortization expense [Abstract]
Total depreciation and amortization expense	582.5	568.4	597.4
Capital spending [Abstract]
Total capital spending	200.6	298.9	385.6
Assets
Total assets	8,517.7	8,270.9		8,517.7
Chlor Alkali Products and Vinyls
Sales [Abstract]
Sales	4,140.8	2,959.9	3,420.1
Income (loss) before taxes [Abstract]
Income (loss) before taxes	(997.8)	(3.5)	(336.7)
Goodwill, Impairment Loss		557.6
Depreciation and amortization expense [Abstract]
Total depreciation and amortization expense	466.4	451.4	470.4
Capital spending [Abstract]
Total capital spending	130.2	180.4	240.3
Assets
Total assets	6,184.9	6,165.5		6,184.9
Epoxy
Sales [Abstract]
Sales	3,186.0	1,870.5	2,024.4
Income (loss) before taxes [Abstract]
Income (loss) before taxes	(616.5)	(40.8)	(53.9)
Goodwill, Impairment Loss		142.2
Depreciation and amortization expense [Abstract]
Total depreciation and amortization expense	86.1	90.7	100.1
Capital spending [Abstract]
Total capital spending	31.0	33.7	30.0
Assets
Total assets	1,307.3	1,153.2		1,307.3
Winchester
Sales [Abstract]
Sales	1,583.8	927.6	665.5
Income (loss) before taxes [Abstract]
Income (loss) before taxes	(412.1)	(92.3)	(40.1)
Depreciation and amortization expense [Abstract]
Total depreciation and amortization expense	23.3	20.1	20.1
Capital spending [Abstract]
Total capital spending	28.5	24.5	12.1
Assets
Total assets	540.6	468.2		540.6
Corporate/Other
Income (loss) before taxes [Abstract]
Environmental expense	(14.0)	(20.9)	(20.5)
Other corporate and unallocated costs	(135.1)	(154.3)	(156.3)
Restructuring charges	(27.9)	(9.0)	(76.5)
Depreciation and amortization expense [Abstract]
Total depreciation and amortization expense	6.7	6.2	6.8
Capital spending [Abstract]
Total capital spending	10.9	60.3	$ 103.2
Assets
Total assets	$ 484.9	$ 484.0		$ 484.9