EMPLOYEE BENEFITS - Schedule of Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Pension Plan
Defined Contribution Plan Disclosure [Line Items]
2020	$ 320.1
2021	328.7
2022	337.5
2023	346.5
2024	352.4
2025-2029	1,813.1
Other Postretirement Benefits Plan
Defined Contribution Plan Disclosure [Line Items]
2020	58.1
2021	57.9
2022	57.3
2023	56.8
2024	56.2
2025-2029	$ 264.7

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=118255775&loc=d3e1928-114920

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