EMPLOYEE BENEFITS - Schedule of Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2017 USD ($)
Pension Plan
Defined Contribution Plan Disclosure [Line Items]
2018	$ 296.5
2019	304.7
2020	311.1
2021	320.8
2022	329.4
2023-2026	1,739.7
Other Postretirement Benefits Plan
Defined Contribution Plan Disclosure [Line Items]
2018	56.8
2019	57.1
2020	57.3
2021	57.5
2022	57.4
2023-2026	$ 279.3

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://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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