Balance Sheet Information - Property, Plant and Equipment, Net (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 26, 2020	Dec. 27, 2019
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements net excluding construction in progress	$ 191.7	$ 178.1
Accumulated depreciation	(68.3)	(56.7)
Construction in progress	24.7	23.9
Total	$ 148.1	145.3
Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	50 years
Land [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 4.4	4.8
Buildings [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 33.5	36.9
Property, plant and equipment, useful life	50 years
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 64.8	58.1
Machinery and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Machinery and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 45.1	41.8
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 39.6	32.1
Computer Equipment and Software [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Computer Equipment and Software [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 4.3	$ 4.4
Property, plant and equipment, useful life	5 years

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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- Definition

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.

+ References

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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