Depreciation and Amortization (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2015	Feb. 28, 2014	Dec. 31, 2014
Depreciation and Amortization [Abstract]
Depreciation expense	$ 311us-gaap_Depreciation	$ 258us-gaap_Depreciation	$ 567us-gaap_Depreciation	$ 520us-gaap_Depreciation
Intangible asset and other amortization	196	73	259	143
Total depreciation and amortization expense	507	331	826	663
Business Acquisition [Line Items]
Ownership percentage (in hundredths)	45.00%		45.00%
Depreciation and amortization expense included in inventory step-up amortization	106		106
Alliance Boots [Member]
Business Acquisition [Line Items]
Remaining ownership percentage (in hundredths)					55.00%
Ownership percentage (in hundredths)	100.00%	45.00%	100.00%	45.00%	45.00%
Depreciation and amortization expense included in inventory step-up amortization	$ 106		$ 106

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

+ Details

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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- Details

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

+ 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

Fair value portion of inventory expected to be realized or consumed after one year or normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19190-110258

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

+ References

No definition available.

+ Details

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- Details

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