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Post-Retirement Health Care (Components of Net Periodic Post-retirement Benefit Cost) (Details) - Scenario, Forecast - Postretirement Health Coverage $ in Thousands | 12 Months Ended
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Dec. 28, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items] |
Service cost | $ 680
Interest cost | 795
Amortization of net (gain) loss | 0
Net periodic post-retirement benefit cost | $ 1,475

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