Acquisitions, Unaudited pro forma results prepared for comparative purposes (Details) (Alliance Boots [Member], USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2015	Feb. 28, 2014
Alliance Boots [Member]
Business Acquisition [Line Items]
Net sales	$ 30,202	$ 29,276	$ 59,173	$ 56,999
Net earnings	$ 1,253	$ 966	$ 2,621	$ 1,973
Net earnings per common share [Abstract]
Basic (in dollars per share)	$ 1.20	$ 0.88	$ 2.51	$ 1.80
Diluted (in dollars per share)	$ 1.19	$ 0.87	$ 2.49	$ 1.78

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ 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 (h)(2)-(3)

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

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

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