Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 26, 2016	Mar. 28, 2015	Mar. 26, 2016	Mar. 28, 2015
Numerator:
Net income	$ 10,516	$ 13,569	$ 28,877	$ 31,593
Denominator:
Weighted-average shares outstanding	5,514,381	5,793,799	5,536,656	5,818,441
Effect of dilutive securities	26,505	41,059	30,850	39,889
Weighted-average diluted shares	5,540,886	5,834,858	5,567,506	5,858,330
Basic earnings per share	$ 1.91	$ 2.34	$ 5.22	$ 5.43
Diluted earnings per share	$ 1.90	$ 2.33	$ 5.19	$ 5.39