Stockholder's Equity (Share Based Compensation) (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 01, 2021	Dec. 27, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Document Period End Date	Jan. 01, 2021
Share-based compensation expense	$ 44.5	$ 33.6
Cost of sales [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	6.4	4.2
Research and development [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	20.3	14.8
Selling, general and administrative [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	$ 17.8	$ 14.6