GOODWILL AND OTHER INTANGIBLE ASSETS - Summary of Goodwill (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Goodwill [Line Items]
Goodwill	$ 8,854	$ 8,796
Goodwill, Foreign Currency Translation Gain (Loss)	60
Rail Infrastructure Operations and Assets [Member]
Goodwill [Line Items]
Goodwill, Written off Related to Sale of Business Unit	(2)
Packaging & Specialty Plastics [Member]
Goodwill [Line Items]
Goodwill	5,112	5,109
Goodwill, Foreign Currency Translation Gain (Loss)	5
Packaging & Specialty Plastics [Member] \| Rail Infrastructure Operations and Assets [Member]
Goodwill [Line Items]
Goodwill, Written off Related to Sale of Business Unit	(2)
Industrial Intermediates & Infrastructure [Member]
Goodwill [Line Items]
Goodwill	1,102	1,100
Goodwill, Foreign Currency Translation Gain (Loss)	2
Industrial Intermediates & Infrastructure [Member] \| Rail Infrastructure Operations and Assets [Member]
Goodwill [Line Items]
Goodwill, Written off Related to Sale of Business Unit	0
Performance Materials & Coatings [Member]
Goodwill [Line Items]
Goodwill	2,640	$ 2,587
Goodwill, Foreign Currency Translation Gain (Loss)	53
Performance Materials & Coatings [Member] \| Rail Infrastructure Operations and Assets [Member]
Goodwill [Line Items]
Goodwill, Written off Related to Sale of Business Unit	$ 0

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
-URI http://asc.fasb.org/extlink&oid=120320667&loc=SL49117168-202975

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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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 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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