Property, Plant and Equipment - Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 29, 2019	Dec. 28, 2018
Property Plant And Equipment [Abstract]
Machinery and equipment	$ 19,127	$ 19,000
Furniture and fixtures	9,328	9,860
Leasehold improvements	10,030	10,045
Total property, plant and equipment, gross	38,485	38,905
Less accumulated depreciation	27,185	27,454
Total property, plant and equipment, net	$ 11,300	$ 11,451

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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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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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.

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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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