Certain Balance Sheet Components (Components Of Property And Equipment) (Details) - USD ($) $ in Millions	Dec. 29, 2017	Dec. 30, 2016
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 424.7	$ 358.1
Less: accumulated depreciation	(250.7)	(213.9)
Total	174.0	144.2
Machinery And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	130.6	113.3
Software License Arrangement [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	124.4	119.4
Furniture And Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	29.3	26.3
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	36.6	32.1
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	32.9	10.8
Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	60.9	47.9
Land [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 10.0	$ 8.3

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Section 50
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-Name Accounting Standards Codification
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
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