Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

No definition available.

Name:	us-gaap_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Asset Purchase Agreement, Expected Payment To Acquire Productive Assets

No definition available.

Name:	wba_AssetPurchaseAgreementExpectedPaymentToAcquireProductiveAssets
Namespace Prefix:	wba_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

Early Contract Termination Fees

No definition available.

Name:	wba_EarlyContractTerminationFees
Namespace Prefix:	wba_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Merger Related Liabilities, Reimbursement of Transaction Costs

No definition available.