EMPLOYEE BENEFITS - Schedule of Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2018 USD ($)
Pension Plan
Defined Contribution Plan Disclosure [Line Items]
2019	$ 308.5
2020	310.4
2021	318.8
2022	326.6
2023	335.6
2023-2027	1,764.1
Other Postretirement Benefits Plan
Defined Contribution Plan Disclosure [Line Items]
2019	58.4
2020	58.5
2021	58.6
2022	58.3
2023	57.8
2023-2027	$ 277.4

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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