Goodwill and Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 29, 2018	Sep. 29, 2017
Finite-Lived Intangible Assets [Line Items]
Total intangible assets, Gross Carrying Amount	$ 251.0	$ 242.4
Total intangible assets, Accumulated Amortization	(191.1)	(174.6)
Total intangible assets, Net Carrying Amount	$ 59.9	67.8
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	5 years
Gross Carrying Amount	$ 78.5	78.5
Accumulated Amortization	(66.9)	(63.4)
Net Carrying Amount	$ 11.6	15.1
Developed technology and other [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	5 years
Gross Carrying Amount	$ 152.9	150.2
Accumulated Amortization	(119.0)	(110.9)
Net Carrying Amount	$ 33.9	39.3
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	3 years
Gross Carrying Amount	$ 1.6	1.6
Accumulated Amortization	(0.7)	(0.3)
Net Carrying Amount	$ 0.9	1.3
Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	3 years
Gross Carrying Amount	$ 18.0	12.1
Accumulated Amortization	(4.5)	0.0
Net Carrying Amount	$ 13.5	$ 12.1