Certain Balance Sheet Components (Components Of Property And Equipment) (Details) - USD ($) $ in Millions	Jan. 03, 2020	Dec. 28, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 557.6	$ 475.0
Less: accumulated depreciation	(316.2)	(262.1)
Total	241.4	212.9
Machinery And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	165.3	134.2
Software License Arrangement [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	143.0	135.9
Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	115.3	106.5
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	49.9	40.7
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	38.3	16.4
Furniture And Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	35.7	31.4
Land [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 10.1	$ 9.9

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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