Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(2))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

Refers additional ownership indirect economic interest.

+ References

No definition available.

+ Details

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- Definition

Amount of previously unrecognized capital loss deferred tax assets to recognize during the period.

+ References

No definition available.

+ Details

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- Details

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Basis of Presentation (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Nov. 30, 2014	Nov. 30, 2013	Aug. 31, 2014
Schedule of Equity Method Investments [Line Items]
Additional ownership interest, indirect (in hundredths)	72.50%wag_AdditionalOwnershipInterestIndirect
Effective tax rate (in hundredths)	26.40%	36.80%
Discrete tax benefit	$ 86wag_DiscreteTaxBenefit
Alliance Boots [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage (in hundredths)	45.00%	45.00%	45.00%
Walgreens Boots Alliance Development GmbH [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage (in hundredths)	50.00%
Ownership percentage of WBA (in hundredths)	100.00%