Number of shares of equity interests issued or issuable to acquire entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

+ Details

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

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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

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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

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585

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Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Represents equity method ownership option to repurchase shares amount.

+ References

No definition available.

+ Details

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Organization (Details) £ in Millions			3 Months Ended
Organization (Details) £ in Millions	Dec. 31, 2014 USD ($) shares	Dec. 31, 2014 GBP (£) shares	Nov. 30, 2015 USD ($) Segment shares	Aug. 31, 2015 shares	Jan. 01, 2015 shares
Schedule of Equity Method Investments [Line Items]
Number of reportable segment \| Segment			3
Total purchase price cash consideration	$ 4,900,000,000	£ 3,133
Ownership percentage			45.00%
Common shares transfer (in shares)			1,172,513,618	1,172,513,618
Walgreens Boots Alliance [Member]
Schedule of Equity Method Investments [Line Items]
Increased ownership percentage of Alliance Boots	55.00%	55.00%
Total purchase price cash consideration \| £		£ 3,133
Number of shares exchanged in acquisition (in shares)	144.3	144.3
Noncontrolling interest	55.00%	55.00%
Walgreens Boots Alliance Development GmbH [Member]
Schedule of Equity Method Investments [Line Items]
Increased ownership percentage of Alliance Boots			27.50%
Noncontrolling interest			27.50%
Ownership interest percentage prior to Second Step Transaction			50.00%
Ownership percentage			72.50%
Alliance Boots [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	45.00%	45.00%
Alliance Healthcare Italia Distribuzione S.p.A. [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage					5.00%
Common shares transfer (in shares)					320
Equity method ownership option to repurchase shares, amount \| $			$ 100,000