Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Sep. 03, 2017	Aug. 28, 2016	Aug. 30, 2015
Statement of Comprehensive Income [Abstract]
NET INCOME INCLUDING NONCONTROLLING INTERESTS	$ 2,714	$ 2,376	$ 2,409
Foreign-currency translation adjustment and other, net	98	26	(1,063)
Comprehensive income	2,812	2,402	1,346
Less: Comprehensive income attributable to noncontrolling interests	48	30	14
COMPREHENSIVE INCOME ATTRIBUTABLE TO COSTCO	$ 2,764	$ 2,372	$ 1,332

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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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