SEGMENTS AND GEOGRAPHIC REGIONS Significant Items (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs		$ (63)		$ (174)
Restructuring Charges	$ (16)	(617)	$ (69)	(719)
Charges related to separation, distribution and tax matters agreements	0		(5)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal		220		220
Gain (Loss) on Extinguishment of Debt	(472)	63	(574)	(149)
Other Nonrecurring (Income) Expense	(474)	(523)	(715)	(816)
Digitalization program costs	(40)		(121)
Luxi Chemical Group Breach of Contract Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement	54		54
Nova Ethylene Asset Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement		0		6
Packaging & Specialty Plastics [Member]
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs		0		0
Restructuring Charges	0	(18)	(8)	(30)
Charges related to separation, distribution and tax matters agreements	0		0
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal		35		35
Gain (Loss) on Extinguishment of Debt	0	0	0	0
Other Nonrecurring (Income) Expense	0	17	(8)	11
Digitalization program costs	0		0
Packaging & Specialty Plastics [Member] \| Luxi Chemical Group Breach of Contract Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement	0		0
Packaging & Specialty Plastics [Member] \| Nova Ethylene Asset Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement		0		6
Industrial Intermediates & Infrastructure [Member]
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs		0		0
Restructuring Charges	0	(22)	(1)	(22)
Charges related to separation, distribution and tax matters agreements	0		0
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal		0		0
Gain (Loss) on Extinguishment of Debt	0	0	0	0
Other Nonrecurring (Income) Expense	54	(22)	53	(22)
Digitalization program costs	0		0
Industrial Intermediates & Infrastructure [Member] \| Luxi Chemical Group Breach of Contract Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement	54		54
Industrial Intermediates & Infrastructure [Member] \| Nova Ethylene Asset Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement		0		0
Performance Materials & Coatings [Member]
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs		0		0
Restructuring Charges	0	(189)	(10)	(189)
Charges related to separation, distribution and tax matters agreements	0		0
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal		0		0
Gain (Loss) on Extinguishment of Debt	0	0	0	0
Other Nonrecurring (Income) Expense	0	(189)	(10)	(189)
Digitalization program costs	0		0
Performance Materials & Coatings [Member] \| Luxi Chemical Group Breach of Contract Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement	0		0
Performance Materials & Coatings [Member] \| Nova Ethylene Asset Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement		0		0
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs		(63)		(174)
Restructuring Charges	(16)	(388)	(50)	(478)
Charges related to separation, distribution and tax matters agreements	0		(5)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal		185		185
Gain (Loss) on Extinguishment of Debt	(472)	63	(574)	(149)
Other Nonrecurring (Income) Expense	(528)	(329)	(750)	(616)
Digitalization program costs	(40)		(121)
Corporate Segment [Member] \| Luxi Chemical Group Breach of Contract Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement	$ 0		$ 0
Corporate Segment [Member] \| Nova Ethylene Asset Matter [Member]
Segment Reporting Information [Line Items]
Gain (Loss) Related to Litigation Settlement		$ 0		$ 0

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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