Balance Sheet Information - Property, Equipment and Leasehold Improvements, Net (Detail) - USD ($) $ in Thousands	Jun. 28, 2019	Dec. 28, 2018
Property, Plant and Equipment [Line Items]
Accumulated depreciation	$ (53,610)	$ (42,501)
Property, equipment and leasehold improvements net excluding construction in progress	128,443	128,447
Construction in progress	16,062	15,012
Total	144,505	143,459
Land [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and leasehold improvements, gross	4,287	4,727
Building [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and leasehold improvements, gross	36,895	32,243
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and leasehold improvements, gross	32,870	31,342
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and leasehold improvements, gross	4,088	5,764
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and leasehold improvements, gross	62,158	57,602
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and leasehold improvements, gross	41,108	38,625
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and leasehold improvements, gross	$ 647	$ 645

Property plant and equipment net excluding construction in progress.

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- Definition

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 of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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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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