Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The fair value of assets acquired in noncash investing or financing activities.

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

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Acquisitions, The Preliminary Identified Definite and Indefinite Lived Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2015	Aug. 31, 2014	Aug. 31, 2013
Indefinite-Lived Intangible Assets [Roll Forward]
Goodwill	$ 14,972	$ 58
Selling, general and administrative expenses	22,571	17,992	$ 17,543
Fair value of the assets acquired	3,700
Estimated manufacturing profit in acquired finished goods inventory capitalized	107
Retail Pharmacy International [Member]
Indefinite-Lived Intangible Assets [Roll Forward]
Goodwill	4,036	0
Retail Pharmacy USA [Member]
Indefinite-Lived Intangible Assets [Roll Forward]
Goodwill	7,290	58
Goodwill arising from synergies	3,500
Goodwill based on a with and without analysis	3,800
Pharmaceutical Wholesale [Member]
Indefinite-Lived Intangible Assets [Roll Forward]
Goodwill	3,646	$ 0
Alliance Boots [Member]
Definite-Lived Intangible Assets [Roll Forward]
Amount	2,545
Indefinite-Lived Intangible Assets [Roll Forward]
Amount	9,146
Goodwill	$ 14,800
Equity interest in Alliance Boots	45.00%
Selling, general and administrative expenses	$ 87
Trade Names and Trademarks [Member] \| Alliance Boots [Member]
Indefinite-Lived Intangible Assets [Roll Forward]
Amount	6,657
Pharmacy Licenses [Member] \| Alliance Boots [Member]
Indefinite-Lived Intangible Assets [Roll Forward]
Amount	$ 2,489
Customer Relationships [Member]
Definite-Lived Intangible Assets [Roll Forward]
Weighted-Average Useful Life	12 years	0 years
Customer Relationships [Member] \| Alliance Boots [Member]
Definite-Lived Intangible Assets [Roll Forward]
Weighted-Average Useful Life	12 years
Amount	$ 1,311
Loyalty Card Holders [Member]
Definite-Lived Intangible Assets [Roll Forward]
Weighted-Average Useful Life	12 years	0 years
Loyalty Card Holders [Member] \| Alliance Boots [Member]
Definite-Lived Intangible Assets [Roll Forward]
Weighted-Average Useful Life	12 years
Amount	$ 742
Trade Names and Trademarks [Member] \| Alliance Boots [Member]
Definite-Lived Intangible Assets [Roll Forward]
Weighted-Average Useful Life	7 years
Amount	$ 399
Favorable Lease Interests [Member] \| Alliance Boots [Member]
Definite-Lived Intangible Assets [Roll Forward]
Weighted-Average Useful Life	8 years
Amount	$ 93