SEGMENTS AND GEOGRAPHIC REGIONS Significant Items (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs	$ (63)	$ (164)	$ (174)	$ (914)
Restructuring Charges	(617)	(147)	(719)	(368)
Accrual for Environmental Loss Contingencies, Revision in Estimates		(399)		(399)
Gain (Loss) on Extinguishment of Debt	(63)	0	(149)	(44)
Other Nonrecurring (Income) Expense	(523)	(466)	(816)	(1,652)
Gain (Loss) Related to Litigation Settlement	0	205	6	205
Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties		39		39
Charges related to separation, distribution and tax matters agreements		0		(127)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	220	0	220	(44)
Packaging & Specialty Plastics [Member]
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs	0	0	0	0
Restructuring Charges	(18)	(31)	(30)	(50)
Accrual for Environmental Loss Contingencies, Revision in Estimates		(5)		(5)
Gain (Loss) on Extinguishment of Debt	0	0	0	0
Other Nonrecurring (Income) Expense	17	134	11	115
Gain (Loss) Related to Litigation Settlement	0	170	6	170
Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties		0		0
Charges related to separation, distribution and tax matters agreements		0		0
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	35	0	35	0
Industrial Intermediates & Infrastructure [Member]
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs	0	0	0	0
Restructuring Charges	(22)	(5)	(22)	(5)
Accrual for Environmental Loss Contingencies, Revision in Estimates		(8)		(8)
Gain (Loss) on Extinguishment of Debt	0	0	0	0
Other Nonrecurring (Income) Expense	(22)	(13)	(22)	(13)
Gain (Loss) Related to Litigation Settlement	0	0	0	0
Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties		0		0
Charges related to separation, distribution and tax matters agreements		0		0
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	0	0	0	0
Performance Materials & Coatings [Member]
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs	0	0	0	0
Restructuring Charges	(189)	(10)	(189)	(32)
Accrual for Environmental Loss Contingencies, Revision in Estimates		(50)		(50)
Gain (Loss) on Extinguishment of Debt	0	0	0	0
Other Nonrecurring (Income) Expense	(189)	(60)	(189)	(82)
Gain (Loss) Related to Litigation Settlement	0	0	0	0
Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties		0		0
Charges related to separation, distribution and tax matters agreements		0		0
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	0	0	0	0
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Business Combination, Integration Related Costs	(63)	(164)	(174)	(914)
Restructuring Charges	(388)	(101)	(478)	(281)
Accrual for Environmental Loss Contingencies, Revision in Estimates		(336)		(336)
Gain (Loss) on Extinguishment of Debt	(63)	0	(149)	(44)
Other Nonrecurring (Income) Expense	(329)	(527)	(616)	(1,672)
Gain (Loss) Related to Litigation Settlement	0	35	0	35
Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties		39		39
Charges related to separation, distribution and tax matters agreements		0		(127)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	$ 185	$ 0	$ 185	$ (44)

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Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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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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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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