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Retirement Plans (Schedule Of Future Cash Flows) (Details) - USD ($) | 4 Months Ended |
--- | --- | ---
Jan. 20, 2019 | Jan. 01, 2018
Defined Benefit Plan Disclosure [Line Items] |  |
Minimum required contribution for retirement plans |  | $ 0
SERP |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Net year-to-date contributions | $ 1,763,000 |
Remaining estimated net contributions during fiscal 2019 | 3,300,000 |
Postretirement Healthcare Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Net year-to-date contributions | 348,000 |
Remaining estimated net contributions during fiscal 2019 | $ 1,000,000 |

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