Nature of Operations and Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Nature of Operations and Summary of Significant Accounting Policies
Land	$ 1,943	$ 1,943
Buildings and leasehold improvements	16,831	16,768
Machinery and equipment	24,721	27,458
Total cost	43,495	46,169
Accumulated depreciation and amortization	(28,384)	(30,671)
Property, Plant and Equipment, Net, Total	$ 15,111	$ 15,498

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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- Definition

Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

+ References

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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