Employee Stock and Benefit Plans (Stock-Based Compensation Expense Recognized in the Consolidated Financial Statements) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Oct. 02, 2016
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 250.3	$ 176.0	$ 218.1
Total related tax benefit	62.4	57.6	73.0
Total capitalized stock-based compensation included in net property, plant and equipment and inventories on the consolidated balance sheets	3.5	1.9	1.5
Stock Options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	28.0	44.3	42.7
Restricted Stock Units (RSUs) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 222.3	$ 131.7	$ 175.4