Summary of Significant Accounting Policies - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Jul. 01, 2017	Jun. 25, 2016	Jul. 01, 2017	Jun. 25, 2016
Numerator:
Net income	$ 8,717	$ 7,796	$ 37,637	$ 36,673
Denominator:
Weighted-average shares outstanding (in shares)	5,195,088	5,443,058	5,239,847	5,505,456
Effect of dilutive securities (in shares)	38,411	29,723	34,547	30,475
Weighted-average diluted shares (in shares)	5,233,499	5,472,781	5,274,394	5,535,931
Basic earnings per share (in dollars per share)	$ 1.68	$ 1.43	$ 7.18	$ 6.66
Diluted earnings per share (in dollars per share)	$ 1.67	$ 1.42	$ 7.14	$ 6.62