Number of states or provinces within a country where Costco has warehouses

No definition available.

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- Definition

Number of warehouses operated by country

+ References

No definition available.

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- Definition

Percentage of Ownership Interest Acquired

+ References

No definition available.

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- Definition

The aggregate foreign currency transaction gain (loss) (both realized and unrealized) included in determining net income for the reporting period. Excludes foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements. For certain enterprises, primarily banks, that are dealers in foreign exchange, foreign currency transaction gains (losses) may be disclosed as dealer gains (losses).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 52

-Paragraph 30

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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-Section 45

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Reflects the difference between (a) inventory at the lower of LIFO cost or market and (b) inventory at replacement cost or at the lower of some acceptable inventory accounting method (such as FIFO or average cost), or market. If material, reflects an excess of replacement or current cost over stated LIFO value parenthetically on the balance sheet or in a note to the financial statements.

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(c))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph c

-Article 5

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- Definition

The change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods, which change has been reflected in the statement of income during the period.

+ References

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section L

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- Definition

Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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Summary of Significant Policies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended					1 Months Ended	3 Months Ended
	Nov. 25, 2012	Nov. 20, 2011	Sep. 02, 2012	Nov. 25, 2012 Forward Foreign Exchange Contracts	Sep. 02, 2012 Forward Foreign Exchange Contracts	Jul. 31, 2012 Costco Mexico	Nov. 25, 2012 UNITED STATES	Nov. 25, 2012 CANADA	Nov. 25, 2012 MEXICO	Nov. 25, 2012 UNITED KINGDOM	Nov. 25, 2012 JAPAN	Nov. 25, 2012 TAIWAN, PROVINCE OF CHINA	Nov. 25, 2012 KOREA, REPUBLIC OF	Nov. 25, 2012 AUSTRALIA
Summary Of Significant Accounting Policies [Line Items]
Number of warehouses operated	617						447	83	32	22	13	9	8	3
Number of regions in country							41	9
Purchase of equity interest						50.00%
Charge to merchandise costs	$ 2	$ 0
Inventory LIFO reserve	106		108
Notional amount of forward foreign - exchange derivative				267	284
Gain (loss) on foreign currency transaction	$ 9	$ 20