RETIREMENT BENEFITS - Defined Contribution Plans and Postemployment Plans (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Postemployment Retirement Benefits
Service-related expense
Interest cost on benefit obligation	$ 0	$ 0	$ 1	$ 2
Amortization of unrecognized
Prior service benefit	(8)	(7)	(23)	(23)
Net actuarial loss	1	1	2	3
Total service-related benefit	(7)	(6)	(20)	(18)
Non-service-related expense (benefit)	9	10	21	23
Total net (benefit) expense	2	4	1	5
U.S. \| Postretirement Benefit Plans
Defined Contribution Plans
Company's contributions for defined contribution plans	95	89	293	281
Amortization of unrecognized
Total net (benefit) expense	7	4	15	11
Non-U.S. plans \| Postretirement Benefit Plans
Defined Contribution Plans
Company's contributions for defined contribution plans	68	67	203	207
Amortization of unrecognized
Total net (benefit) expense	$ 12	$ 10	$ 34	$ 31

Represents the non-service related expense for defined benefit plans for the period.

No definition available.

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- Definition

Represents the service related expense for defined benefit plans for the period.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

+ Details

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- Definition

Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

+ References

+ Details

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- Definition

Amount of cost recognized for passage of time related to defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

+ Details

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- References

No definition available.

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- References

No definition available.

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- References

No definition available.

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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