Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 27, 2020	Sep. 28, 2019
Statement of Financial Position [Abstract]
Accounts receivable, reserves	$ 27.2	$ 17.8
Preferred stock, par value (in dollars per share)	$ 10,000.00	$ 10,000.00
Preferred stock, authorized (in shares)	1,623,000,000	1,623,000,000
Preferred stock, issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 10,000.00	$ 10,000.00
Common stock, authorized (in shares)	750,000,000,000	750,000,000,000
Common stock, issued (in shares)	294,684,000,000	292,323,000,000
Treasury stock (in shares)	35,941,000,000	24,638,000,000