GOODWILL AND INTANGIBLE ASSETS (Details 1) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 2,119.7	$ 2,119.6	$ 2,120.0
Foreign currency translation adjustment	0.1	(0.4)
Chlor Alkali Products and Vinyls
Goodwill [Line Items]
Goodwill	1,832.7	1,832.6	1,832.9
Foreign currency translation adjustment	0.1	(0.3)
Epoxy
Goodwill [Line Items]
Goodwill	287.0	287.0	$ 287.1
Foreign currency translation adjustment	$ 0.0	$ (0.1)

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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