Name:	us-gaap_BusinessAcquisitionLineItems
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

Name:	us-gaap_PaymentsToAcquireBusinessesGross
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Asset Purchase Agreement Consideration to be Transferred

No definition available.

Name:	wba_AssetPurchaseAgreementConsiderationtobeTransferred
Namespace Prefix:	wba_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Asset Purchase Agreement, Number of Distribution Centers Expected To Be Acquired

No definition available.

Name:	wba_AssetPurchaseAgreementNumberofDistributionCentersExpectedToBeAcquired
Namespace Prefix:	wba_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Asset Purchase Agreement, Number of Stores Expected To Be Acquired

No definition available.

Name:	wba_AssetPurchaseAgreementNumberofStoresExpectedToBeAcquired
Namespace Prefix:	wba_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Number of Locations Acquired

No definition available.