Goodwill and Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jan. 01, 2021	Oct. 02, 2020
Finite-Lived Intangible Assets [Line Items]
Document Period End Date	Jan. 01, 2021
Accumulated Amortization	$ (79,500)	$ (113,100)
Total intangible assets, Gross Carrying Amount	125,900	166,600
Total intangible assets, Net Carrying Amount	$ 46,400	53,500
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	5 years
Finite-Lived Intangible Assets, Gross	$ 18,200	18,200
Accumulated Amortization	(16,700)	(15,800)
Net Carrying Amount	$ 1,500	2,400
Technology-Based Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	5 years
Finite-Lived Intangible Assets, Gross	$ 60,900	101,000
Accumulated Amortization	(46,300)	(81,600)
Net Carrying Amount	$ 14,600	19,400
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	3 years
Finite-Lived Intangible Assets, Gross	$ 0	1,600
Accumulated Amortization	0	(1,500)
Net Carrying Amount	$ 0	100
Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	3 years 1 month 6 days
Finite-Lived Intangible Assets, Gross	$ 27,300	26,300
Accumulated Amortization	(16,500)	(14,200)
Net Carrying Amount	10,800	12,100
In Process Research and Development [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	19,500	19,500
Accumulated Amortization	0	0
Net Carrying Amount	$ 19,500	$ 19,500