Retirement Benefit Plans Executive Plan (Details) - Supplemental Employee Retirement Plans, Defined Benefit - USD ($) $ in Thousands	Dec. 29, 2019	Dec. 30, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans
Liability, Defined Benefit Plan	$ 662	$ 1,257
Deferred Compensation Arrangements, Recorded Liability	$ 774	$ 444

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Name:	us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant