Stockholder's Equity (Share Based Compensation) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Document Period End Date			Jun. 26, 2020
Share-based compensation expense	$ 37.8	$ 16.0	$ 111.6	$ 58.6
Cost of sales [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	4.7	1.3	16.1	8.2
Research and development [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	17.0	9.5	49.0	31.9
Selling, general and administrative [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	$ 16.1	$ 5.2	$ 46.5	$ 18.5