Consolidated Statements Of Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
Aug. 31, 2014	Sep. 01, 2013	Sep. 02, 2012
Statement of Comprehensive Income [Abstract]
NET INCOME INCLUDING NONCONTROLLING INTERESTS	$ 2,088	$ 2,061	$ 1,767
Foreign-currency translation adjustment and other, net	49	(278)	(96)
Comprehensive income	2,137	1,783	1,671
Less: Comprehensive income attributable to noncontrolling interests	33	22	24
COMPREHENSIVE INCOME ATTRIBUTABLE TO COSTCO	$ 2,104	$ 1,761	$ 1,647

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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