Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	8 Months Ended
May 07, 2017	May 08, 2016	May 07, 2017	May 08, 2016
Statement of Comprehensive Income [Abstract]
NET INCOME INCLUDING NONCONTROLLING INTERESTS	$ 706	$ 549	$ 1,782	$ 1,591
Foreign-currency translation adjustment and other, net	21	224	(210)	(5)
Comprehensive income	727	773	1,572	1,586
Less: Comprehensive income attributable to noncontrolling interests	15	10	34	20
COMPREHENSIVE INCOME ATTRIBUTABLE TO COSTCO	$ 712	$ 763	$ 1,538	$ 1,566

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
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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

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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.

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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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