Benefit Plans - Additional Information (Details) $ in Millions	3 Months Ended
	Dec. 30, 2017 USD ($) shares	Dec. 31, 2016 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance under stock plans (in shares) | shares	273,400,000
Income tax benefit related to share-based compensation expense	$ 631	$ 465
Total unrecognized compensation cost related to RSUs, restricted stock and stock options	$ 12,100
Total unrecognized compensation cost related to RSUs, restricted stock and stock options, weighted-average recognition period	2 years 11 months
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs granted, vesting period	4 years
Number of shares of common stock issued per RSU upon vesting	1
Reduction in number of shares available for grant per share issued with respect to RSUs granted (in shares) | shares	2
Factor by which each RSU canceled or share withheld for taxes increases the number of shares available for grant	2
Fair value of vested RSUs as of vesting date	$ 3,100	$ 2,200