Stockholder's Equity (Share Based Compensation) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 28, 2019	Jun. 29, 2018	Jun. 28, 2019	Jun. 29, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	$ 16.0	$ 19.5	$ 58.6	$ 86.3
Cost of sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	1.3	3.3	8.2	11.6
Research and development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	9.5	6.5	31.9	32.2
Selling, general and administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	$ 5.2	$ 9.7	$ 18.5	$ 42.5