DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Pension and Other Post-Retirement Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Decrease in company's benefit obligations from new mortality improvement scales	$ 5.2	$ 1.3

Defined Benefit Plan, Actuarial Gain (Loss), Change in Mortality Assumptions

No definition available.

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