Certain Balance Sheet Components (Components Of Property And Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Jan. 01, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 596.2	$ 598.1
Less: accumulated depreciation	(363.0)	(346.3)
Total property and equipment, net	233.2	251.8
Land, building, furniture, and leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	238.8	253.3
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	185.8	178.7
Software and licenses
Property, Plant and Equipment [Line Items]
Property and equipment, gross	150.9	148.9
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20.7	$ 17.2

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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