Balance Sheet Details - Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Property, Plant and Equipment [Line Items]
Property plant and equipment	$ 61,711	$ 59,955
Less accumulated depreciation and amortization	50,113	48,757
Total property, plant and equipment, net	11,598	11,198
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment	15,037	14,923
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment	$ 46,674	$ 45,032

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, 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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