Employee Stock and Benefit Plans (Stock-Based Compensation Expense Recognized in the Consolidated Financial Statements) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 30, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 248.5	$ 308.0	$ 250.3
Total related tax benefit	47.8	59.3	62.4
Total capitalized stock-based compensation included in net property, plant and equipment on the consolidated balance sheets	3.6	3.4	3.5
Stock Options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	7.5	20.0	28.0
Restricted Stock Units (RSUs) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 241.0	$ 288.0	$ 222.3