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DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Pension and Other Post-Retirement Benefit Plans (Details) - USD ($) $ in Millions | 12 Months Ended
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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

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- Definition Defined Benefit Plan, Actuarial Gain (Loss), Change in Mortality Assumptions + References No definition available. + Details
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