Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Millions	Total	Total Costco Stockholders' Equity	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Noncontrolling Interests
Dividends declared	$ 1.70
Common stock at beginning of period (shares) at Aug. 30, 2015			437,952
Equity at beginning of period at Aug. 30, 2015	$ 10,843	$ 10,617	$ 2	$ 5,218	$ (1,121)	$ 6,518	$ 226
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,376	2,350				2,350	26
Foreign-currency translation adjustment and other, net	26	22			22		4
Stock-based compensation	459	459		459
Stock options exercised, including tax effects (shares)			4
Stock options exercised, including tax effects	0	0		0
Release of vested RSUs, including tax effects (shares)			2,749
Release of vested RSUs, including tax effects	(146)	(146)		(146)
Conversion of convertible notes (shares)			3
Conversion of convertible notes	$ 0	0		0
Stock Repurchased and Retired During Period, Shares	(3,184)		(3,184)
Stock Repurchased and Retired During Period, Value	$ (477)	(477)		(41)		(436)
Cash dividends declared and other	(749)	(746)				(746)	(3)
Common stock at end of period (shares) at Aug. 28, 2016			437,524
Equity at end of period at Aug. 28, 2016	$ 12,332	12,079	$ 2	5,490	(1,099)	7,686	253
Dividends declared	$ 8.90
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 2,714	2,679				2,679	35
Foreign-currency translation adjustment and other, net	98	85			85		13
Stock-based compensation	518	518		518
Release of vested RSUs, including tax effects (shares)			2,673
Release of vested RSUs, including tax effects	(165)	(165)		(165)
Conversion of convertible notes (shares)			5
Conversion of convertible notes	$ 0	0	$ 0	0
Stock Repurchased and Retired During Period, Shares	(2,998)		(2,998)
Stock Repurchased and Retired During Period, Value	$ (473)	(473)		(41)		(432)
Stockholders' Equity, Other			$ 2	(2)
Cash dividends declared and other	$ (3,945)	(3,945)				(3,945)
Common stock at end of period (shares) at Sep. 03, 2017	437,204		437,204
Equity at end of period at Sep. 03, 2017	$ 11,079	10,778	$ 4	5,800	(1,014)	5,988	301
Dividends declared	$ 2.14
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 3,179	3,134				3,134	45
Foreign-currency translation adjustment and other, net	(192)	(185)			(185)		(7)
Stock-based compensation	547	547		547
Release of vested RSUs, including tax effects (shares)			2,741
Release of vested RSUs, including tax effects	$ (217)	(217)		(217)
Stock Repurchased and Retired During Period, Shares	(1,756)		(1,756)
Stock Repurchased and Retired During Period, Value	$ (322)	(322)		(26)		(296)
Stockholders' Equity, Other				3
Cash dividends declared and other	$ (971)	(936)				(939)	(35)
Common stock at end of period (shares) at Sep. 02, 2018	438,189		438,189
Equity at end of period at Sep. 02, 2018	$ 13,103	$ 12,799	$ 4	$ 6,107	$ (1,199)	$ 7,887	$ 304