Property, Plant, and Equipment, net (Details) - USD ($) $ in Thousands	Jun. 26, 2021	Dec. 26, 2020
Property, Plant and Equipment [Line Items]
Sub-total	$ 376,691	$ 353,335
Less: Accumulated depreciation and amortization	(305,356)	(294,468)
Net, property, plant and equipment	71,335	58,867
Construction-in-process	54,013	45,236
Total	125,348	104,103
Land
Property, Plant and Equipment [Line Items]
Sub-total	4,751	4,751
Machinery and equipment
Property, Plant and Equipment [Line Items]
Sub-total	239,322	226,185
Computer equipment and software
Property, Plant and Equipment [Line Items]
Sub-total	44,273	36,361
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Sub-total	6,924	6,894
Leasehold improvements
Property, Plant and Equipment [Line Items]
Sub-total	$ 81,421	$ 79,144

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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 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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