Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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Amount of the hedged item as of the balance sheet date related to the derivative. For example, the hedged balance on a debt instrument.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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- Definition

Fair value before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

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-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

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Fair value before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

+ References

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- Definition

Fixed interest rate related to the interest rate derivative.

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No definition available.

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

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- Definition

The loss recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (d)(1)

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- Definition

Represents the date that Walgreens entered into a strategic relationship with AmerisourceBergen Corporation

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No definition available.

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Fair value of derivative asset not designated as a hedge, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

No definition available.

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- Definition

The list of dates or date range within which the options may be exercised of the investment subject to option.

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No definition available.

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- Definition

Exercise price for shares eligible for purchase under the warrant during the six month period beginning March 2016.

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No definition available.

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Number of shares eligible for purchase under the warrant during the six month period beginning March 2016.

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- Definition

The loss recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness net.

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No definition available.

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- Definition

The net unamortized fair value changes attributable to the hedged risk that are included in long-term debt.

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No definition available.

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- Definition

Number of shares eligible for purchase in the AmerisourceBergen Corporation agreement.

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No definition available.

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- Definition

Percentage of fully diluted equity eligible for purchase relating to the AmerisourceBergen Corporation agreement.

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No definition available.

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The list of dates or date range within which the options may be exercised of the investment subject to option.

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No definition available.

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Exercise price for shares eligible for purchase under the warrant during the six month period beginning March 2017.

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Number of shares eligible for purchase under the warrant during the six month period beginning March 2017.

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Financial Instruments (Details) In Millions, except Share data, unless otherwise specified	3 Months Ended					3 Months Ended									3 Months Ended
	Nov. 30, 2014 USD ($)	Nov. 30, 2014 EUR (€)	Nov. 30, 2014 GBP (£)	Aug. 31, 2014 USD ($)	Nov. 30, 2013 USD ($)	Nov. 30, 2014 Three-month LIBOR [Member] USD ($)	Nov. 30, 2014 Interest Rate Swap [Member] USD ($)	Aug. 31, 2014 Interest Rate Swap [Member] USD ($)	Nov. 30, 2013 Interest Rate Swap [Member] USD ($)	Nov. 30, 2014 Interest Rate Swap [Member] Interest Rate Contract [Member] Other non-currents assets [Member] USD ($)	Aug. 31, 2014 Interest Rate Swap [Member] Interest Rate Contract [Member] Other non-currents assets [Member] USD ($)	Nov. 30, 2013 Interest Rate Swap [Member] Interest Rate Contract [Member] Other non-currents assets [Member] USD ($)	Nov. 30, 2014 Interest Rate Swap [Member] one-month LIBOR [Member] USD ($)	Nov. 30, 2014 Interest Rate Swap [Member] six-month LIBOR [Member] USD ($)	Nov. 30, 2014 Forward Interest Rate Swaps [Member] USD ($)	Aug. 31, 2014 Forward Interest Rate Swaps [Member] USD ($)	Nov. 30, 2013 Forward Interest Rate Swaps [Member] USD ($)	Nov. 30, 2014 Forward Interest Rate Swaps [Member] Interest Rate Contract [Member] Other Noncurrent Liabilities [Member] USD ($)	Aug. 31, 2014 Forward Interest Rate Swaps [Member] Interest Rate Contract [Member] Other Noncurrent Liabilities [Member] USD ($)	Nov. 30, 2013 Forward Interest Rate Swaps [Member] Interest Rate Contract [Member] Other Noncurrent Liabilities [Member] USD ($)	Nov. 30, 2014 Forward Interest Rate Swaps [Member] Three-month LIBOR [Member] USD ($)	Nov. 30, 2014 Warrants [Member] Other non-currents assets [Member] USD ($)	Aug. 31, 2014 Warrants [Member] Other non-currents assets [Member] USD ($)	Nov. 30, 2013 Warrants [Member] Other non-currents assets [Member] USD ($)	Nov. 30, 2014 Foreign currency forwards [Member] Other current liabilities [Member] USD ($)	Aug. 31, 2014 Foreign currency forwards [Member] Other current liabilities [Member] USD ($)	Nov. 30, 2013 Foreign currency forwards [Member] Other current liabilities [Member] USD ($)
Derivative [Line Items]
Amount of hedged debt							$ 1,000	$ 1,000	$ 1,000						$ 0	$ 1,500	$ 0
Interest rate swaps designated as hedges													250	750							1,500
Fixed interest rate percentage (in hundredths)													5.25%	5.25%
Debt instrument, maturity date, description															expected maturity tenures of 10 and 30 years.
Cash flow hedges terminated upon issuance of hedged debt, gross						63
Cash flow hedges terminated upon issuance of hedged debt, net of tax						39
Derivatives, Fair Value [Line Items]
Fair value of derivative asset designated as hedging instrument										26	16	23
Derivative Liability, Fair Value, Gross Liability																		0	44	0
Fair value of derivative asset not designated as hedging instrument																						844	553	408
Fair value of derivative liability not designated as hedging instrument																									96	0	0
Net unamortized fair value changes in long-term debt	22			12	21
First option exercise date	Mar. 31, 2016	Mar. 31, 2016	Mar. 31, 2016
Second option exercise date	Mar. 31, 2017	Mar. 31, 2017	Mar. 31, 2017
First warrant to purchase shares (shares)	11,348,456wag_FirstWarrantToPurchaseShares	11,348,456wag_FirstWarrantToPurchaseShares	11,348,456wag_FirstWarrantToPurchaseShares
First warrant to purchase shares (dollars per share)	$ 51.50wag_FirstWarrantToPurchasePerShare
Second warrant to purchase shares (shares)	11,348,456wag_SecondWarrantToPurchaseShares	11,348,456wag_SecondWarrantToPurchaseShares	11,348,456wag_SecondWarrantToPurchaseShares
Second warrant to purchase shares (dollars per share)	$ 52.50wag_SecondWarrantToPurchasePerShare
Date of AmerisourceBergen Corporation deal	Mar. 20, 2013	Mar. 20, 2013	Mar. 20, 2013
Number of shares eligible for purchase (in shares)	19,859,795wag_NumberOfSharesEligibleForPurchase	19,859,795wag_NumberOfSharesEligibleForPurchase	19,859,795wag_NumberOfSharesEligibleForPurchase
Percentage of fully diluted equity eligible for purchase (in hundredths)	7.00%	7.00%	7.00%
Foreign currency forward notional amount		€ 600invest_DerivativeNotionalAmount	£ 4,000invest_DerivativeNotionalAmount