Net Income per Common and Common Equivalent Share - Schedule of Earnings per Share Effect on Net Income and Weighted Averegae Number of Dilutive Potential Common Stock (Details) - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Aug. 29, 2021	Aug. 30, 2020	Sep. 01, 2019
Earnings Per Share [Abstract]
NET INCOME ATTRIBUTABLE TO COSTCO	$ 5,007	$ 4,002	$ 3,659
Weighted average number of common shares used in basic net income per common share	443,089	442,297	439,755
RSUs and other	1,257	1,604	3,168
Weighted average number of common shares and dilutive potential of common stock used in diluted net income per share	444,346	443,901	442,923