RETIREMENT BENEFITS - Estimated Future Benefit Payments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
Reduction in accumulated postretirement benefit obligation due to subsidy	$ 4.0	$ 5.0
Reduction in postretirement expense due to subsidy	0.1	0.2
Subsidy received under the EGWP	15.0	$ 12.9
U.S. \| Pension Plans
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
2018	787.0
2019	814.0
2020	846.0
2021	864.0
2022	876.0
2023-2027	4,480.0
U.S. \| Postretirement Benefit Plans
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
2018	61.0
2019	60.0
2020	59.0
2021	58.0
2022	56.0
2023-2027	248.0
Non-U.S. \| Pension Plans
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
2018	432.0
2019	398.0
2020	425.0
2021	434.0
2022	457.0
2023-2027	2,532.0
Non-U.S. \| Postretirement Benefit Plans
Defined Benefit Plan, Postretirement Medical Plan with Prescription Drug Benefits [Abstract]
2018	65.0
2019	70.0
2020	75.0
2021	81.0
2022	87.0
2023-2027	$ 532.0

Amount of the period's gross receipts received from the prescription drug subsidy under the Employer Group Waiver Plan.

No definition available.

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- Definition

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

+ 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 (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

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

+ References

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- Definition

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.

+ References

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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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- Definition

Amount of decrease in accumulated postretirement benefit obligation for government subsidy related to prescription drug benefits attributed to past service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39689-114964

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- Definition

Amount of (increase) decrease in net periodic benefit cost from government subsidy for prescription drug benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39689-114964

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