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Retirement Plans (Schedule Of Costs Of Retirement Plan) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 26, 2020 | Dec. 28, 2019 | Dec. 29, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension Cost (Reversal of Cost) | $ 6,218 | $ 4,733 | $ 4,423
Retirement savings plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension Cost (Reversal of Cost) | 4,949 | 3,434 | 3,525
Deferred compensation plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension Cost (Reversal of Cost) | 806 | 801 | 508
Supplemental executive retirement plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension Cost (Reversal of Cost) | $ 463 | $ 498 | $ 390

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- Definition 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. + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Details
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