Description Of Business And Accounting Policies (Schedule of Error Corrections and Prior Period Adjustments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Dec. 31, 2021
Reclassification [Line Items]
Total revenue	$ 3,798.7	$ 3,676.3	$ 3,659.1
Amortization of purchased intangible assets	108.7	85.0	87.7
Total cost of sales	1,465.9	1,570.7	1,624.4
As Previously Reported
Reclassification [Line Items]
Total revenue		3,676.3	3,659.1
Amortization of purchased intangible assets		85.0	87.7
Total cost of sales		1,570.7	1,624.4
Product
Reclassification [Line Items]
Total revenue	1,771.7	1,986.1	2,135.2
Cost of sales	875.0	1,040.8	1,086.4
Product | As Previously Reported
Reclassification [Line Items]
Total revenue		2,152.0	2,247.5
Cost of sales		1,046.1	1,090.1
Product | Effect of Change in Presentation
Reclassification [Line Items]
Total revenue		(165.9)	(112.3)
Cost of sales		(5.3)	(3.7)
Subscription and services
Reclassification [Line Items]
Total revenue	2,027.0	1,690.2	1,523.9
Cost of sales	$ 482.2	444.9	450.3
Subscription and services | Effect of Change in Presentation
Reclassification [Line Items]
Total revenue		1,690.2	1,523.9
Cost of sales		444.9	450.3
Service | As Previously Reported
Reclassification [Line Items]
Total revenue		641.3	649.4
Cost of sales		235.7	229.9
Service | Effect of Change in Presentation
Reclassification [Line Items]
Total revenue		(641.3)	(649.4)
Cost of sales		(235.7)	(229.9)
Subscription | As Previously Reported
Reclassification [Line Items]
Total revenue		883.0	762.2
Cost of sales		203.9	216.7
Subscription | Effect of Change in Presentation
Reclassification [Line Items]
Total revenue		(883.0)	(762.2)
Cost of sales		$ (203.9)	$ (216.7)