GOODWILL AND INTANGIBLES (Details 1) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 2,119.1	$ 2,119.6	$ 2,119.6	$ 2,120.0
Foreign currency translation adjustment	(0.5)	(0.4)
Chlor Alkali Products and Vinyls
Goodwill [Line Items]
Goodwill	1,832.2	1,832.6	1,832.6	1,832.9
Foreign currency translation adjustment	(0.4)	(0.3)
Epoxy
Goodwill [Line Items]
Goodwill	286.9	287.0	$ 287.0	$ 287.1
Foreign currency translation adjustment	$ (0.1)	$ (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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
-Section 50
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