SEGMENTS AND GEOGRAPHIC REGIONS Significant Items (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Charges related to separation, distribution and tax matters agreements	$ (127)		$ (127)
Business Combination, Integration Related Costs	(348)	$ (234)	(750)	$ (441)
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain (Loss), Net		(20)	0	20
Restructuring Charges	(65)	(32)	(221)	(104)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	(44)	0	(44)	20
Gain (Loss) on Extinguishment of Debt	(44)		(44)
Other Nonrecurring (Income) Expense	(628)	(286)	(1,186)	(545)
Performance Materials & Coatings [Member]
Segment Reporting Information [Line Items]
Charges related to separation, distribution and tax matters agreements	0		0
Business Combination, Integration Related Costs	0	0	0	0
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain (Loss), Net		(20)		(20)
Restructuring Charges	(22)	(15)	(22)	(14)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	0	0	0	0
Gain (Loss) on Extinguishment of Debt	0		0
Other Nonrecurring (Income) Expense	(22)	(35)	(22)	(34)
Industrial Intermediates & Infrastructure [Member]
Segment Reporting Information [Line Items]
Charges related to separation, distribution and tax matters agreements	0		0
Business Combination, Integration Related Costs	0	0	0	0
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain (Loss), Net		0		0
Restructuring Charges	0	0	0	(11)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	0	0	0	20
Gain (Loss) on Extinguishment of Debt	0		0
Other Nonrecurring (Income) Expense	0	0	0	9
Packaging & Specialty Plastics [Member]
Segment Reporting Information [Line Items]
Charges related to separation, distribution and tax matters agreements	0		0
Business Combination, Integration Related Costs	0	0	0	0
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain (Loss), Net		0		0
Restructuring Charges	(6)	(3)	(19)	(9)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	0	0	0	0
Gain (Loss) on Extinguishment of Debt	0		0
Other Nonrecurring (Income) Expense	(6)	(3)	(19)	(9)
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Charges related to separation, distribution and tax matters agreements	(127)		(127)
Business Combination, Integration Related Costs	(348)	(234)	(750)	(441)
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain (Loss), Net		0		0
Restructuring Charges	(37)	(14)	(180)	(70)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	(44)	0	(44)	0
Gain (Loss) on Extinguishment of Debt	(44)		(44)
Other Nonrecurring (Income) Expense	$ (600)	$ (248)	$ (1,145)	(511)
Dow Silicones Corporation [Member]
Segment Reporting Information [Line Items]
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain (Loss), Net				$ (20)

Charges related to separation, distribution and tax matters agreements

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- Definition

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.

+ References

No definition available.

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In a business combination achieved in stages, this element represents the amount of net gain (loss) recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

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

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of other expense (income) that is infrequent in occurrence or unusual in nature.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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