GOODWILL AND OTHER INTANGIBLE ASSETS (Schedule of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Net goodwill, beginning balance	$ 15,272	$ 12,154
Goodwill, Written off Related to Sale of Business Unit		(15)
Goodwill, Increase from Sale of Joint Venture	48
Goodwill, Impairment Loss	(1,491)
Goodwill, Foreign Currency Translation Gain (Loss)	299	(133)
Goodwill, Translation and Purchase Accounting Adjustments	(5)
Net goodwill, ending balance	13,938	15,272
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| SKC Haas Display Films Group [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(34)
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| Global Ethylene Acrylic Acid (EAA) [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(23)
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| Dow AgroSciences' Corn Seed Business [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	$ (128)
Aniline Plant Acquisition [Member]
Goodwill [Roll Forward]
Goodwill, Acquired During Period		37
Dow Corning Corporation [Member]
Goodwill [Roll Forward]
Goodwill, Acquired During Period		$ 3,229

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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.

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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.

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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.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

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