RETIREMENT BENEFITS - Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2018 USD ($)
U.S. \| Pension Plans
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
2019	$ 797
2020	828
2021	847
2022	857
2023	873
2024-2028	4,365
U.S. \| Postretirement Benefit Plans
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
2019	62
2020	62
2021	61
2022	59
2023	57
2024-2028	252
Non-U.S. \| Pension Plans
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
2019	435
2020	417
2021	426
2022	448
2023	471
2024-2028	2,557
Non-U.S. \| Postretirement Benefit Plans
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
2019	70
2020	75
2021	80
2022	86
2023	92
2024-2028	$ 547

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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