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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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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.

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Acquisitions (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Nov. 30, 2014	Nov. 30, 2013	Aug. 31, 2014
Business Acquisition [Line Items]
Total purchase price (including the assumption of debt)	$ 13
Goodwill	2,356us-gaap_Goodwill	2,491us-gaap_Goodwill	2,359us-gaap_Goodwill
Kerr Drug [Member]
Business Acquisition [Line Items]
Total purchase price (including the assumption of debt)		170
Goodwill		42
Intangible assets		54
Net tangible assets		74
All Other Acquisitions, Excluding Kerr Drug [Member]
Business Acquisition [Line Items]
Intangible assets	10
Fair market value of business acquisitions	$ 3