Discontinued Operations (Environmental Remediation) (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Environmental Remediation Obligations [Abstract]
Accrual for Environmental Loss Contingencies	$ 2,007	$ 1,987

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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-Name Accounting Standards Codification
-Topic 450
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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