Summary of Significant Accounting Policies Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Property, Plant and Equipment [Line Items]
Land	$ 20	$ 1,117
Buildings	341	1,976
Leasehold improvements	8,273	6,530
Machinery and equipment	271,061	190,209
Computer equipment and software	53,471	41,345
Furniture and fixtures	2,629	1,671
Construction in process	3,653	8,969
Property and equipment, gross	339,448	251,817
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	131,169	98,674
Property and equipment, net of accumulated depreciation of $131,169 ($98,674 - 2017)	$ 208,279	$ 153,143

Computer equipment and software, gross

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

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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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