Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 18, 2018	Feb. 12, 2017	Feb. 18, 2018	Feb. 12, 2017
Statement of Comprehensive Income [Abstract]
NET INCOME INCLUDING NONCONTROLLING INTERESTS	$ 713	$ 521	$ 1,364	$ 1,076
Foreign-currency translation adjustment and other, net	150	114	127	(231)
Comprehensive income	863	635	1,491	845
Less: Comprehensive income attributable to noncontrolling interests	22	14	33	19
COMPREHENSIVE INCOME ATTRIBUTABLE TO COSTCO	$ 841	$ 621	$ 1,458	$ 826

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

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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.

+ References

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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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