| Fair Value Measures (Narrative) (Details) - USD ($) | Mar. 28, 2020 | Dec. 28, 2019 | 
|---|---|---|
| Fair Value Measures [Abstract] | ||
| Non-financial assets | $ 0 | $ 0 | 
| X | ||||||||||
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- References No definition available. 
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| X | ||||||||||
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- Definition Nonfinancial Assets Fair Value Disclosure No definition available. 
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