Goodwill (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 1,083
Goodwill acquired during the period	172
Effects of changes in foreign exchange rates	(2)
Ending Balance	1,253
Olefins
Goodwill [Roll Forward]
Beginning Balance	30
Goodwill acquired during the period	0
Effects of changes in foreign exchange rates	0
Ending Balance	30
Vinyls
Goodwill [Roll Forward]
Beginning Balance	1,053
Goodwill acquired during the period	172
Effects of changes in foreign exchange rates	(2)
Ending Balance	$ 1,223

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
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-Section 55
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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