PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSIONS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2017
Pension Plan
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Prior service credit as a result of remeasurement	$ 5.3	$ 16.1

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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