COMMITMENTS AND CONTINGENT LIABILITIES (Guarantees) (Table and Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Guarantor Obligations [Line Items]
Guarantor obligations, maximum future payments	$ 5,680	$ 5,663
Guarantor obligations, recorded liability	170	184
Long-term Debt	$ 20,516	$ 20,517
Performance Guarantee [Member]
Guarantor Obligations [Line Items]
Final expiration	2023	2023
Guarantor obligations, maximum future payments	$ 4,766	$ 4,774
Guarantor obligations, recorded liability	$ 37	$ 49
Residual Value Guarantees [Member]
Guarantor Obligations [Line Items]
Final expiration	2027	2027
Guarantor obligations, maximum future payments	$ 914	$ 889
Guarantor obligations, recorded liability	$ 133	135
Sadara Chemical Company [Member]
Guarantor Obligations [Line Items]
Equity Method Investment, Ownership Percentage	35.00%
Sadara Chemical Company [Member] \| Performance Guarantee [Member]
Guarantor Obligations [Line Items]
Guarantor obligations, maximum future payments	$ 4,400
Sadara Chemical Company [Member] \| Total Project Financing [Member]
Guarantor Obligations [Line Items]
Project Financing, Maximum Borrowing Capacity	12,500
Long-term Debt	$ 12,400	$ 12,400

Final expiration year of guarantees of the reporting entity.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Section 45
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
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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.

+ References

No definition available.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 210
-Section S99
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