Segment Reporting (Details) $ in Millions	3 Months Ended
Nov. 30, 2015 USD ($) Segment	Nov. 30, 2014 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| Segment	3
Equity interest in Alliance Boots	45.00%
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	$ 29,033	$ 19,554
Adjusted Operating Income	1,719	1,118
Cost transformation	(90)
Acquisition-related amortization	(81)	(89)
LIFO provision	(46)	(52)
Store closures and other optimization costs		(28)
Acquisition-related costs	(34)	(24)
Increase in fair market value of warrants		129
Operating Income	1,468	1,054
Retail Pharmacy USA [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	20,370	19,554
Adjusted Operating Income	1,243	1,118
Retail Pharmacy International [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	3,531	0
Adjusted Operating Income	315	0
Pharmaceutical Wholesale [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	5,796	0
Adjusted Operating Income	166	0
Eliminations and Unallocated Items [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	(664)	0
Adjusted Operating Income	(5)	0
Reportable Segments [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	29,033	19,554
Adjusted Operating Income	1,719	1,118
Reportable Segments [Member] \| Retail Pharmacy USA [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	20,370	19,554
Adjusted Operating Income	1,243	1,118
Reportable Segments [Member] \| Retail Pharmacy International [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	3,459	0
Adjusted Operating Income	315	0
Reportable Segments [Member] \| Pharmaceutical Wholesale [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	5,204	0
Adjusted Operating Income	166	0
Reportable Segments [Member] \| Eliminations and Unallocated Items [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	0	0
Intersegment Eliminations [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	0	0
Intersegment Eliminations [Member] \| Retail Pharmacy USA [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	0	0
Intersegment Eliminations [Member] \| Retail Pharmacy International [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	72	0
Intersegment Eliminations [Member] \| Pharmaceutical Wholesale [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	592	0
Intersegment Eliminations [Member] \| Eliminations and Unallocated Items [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	$ (664)	$ 0

The amount of expense recognized in the current period that reflects the allocation of capitalized costs associated with acquisition of business. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: 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=56944662&loc=d3e3602-108585

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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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)
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- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e20148-110875

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-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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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.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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The total amount of adjusted operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

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The aggregate cost incurred for transformation of goods produced and sold and services rendered during the reporting period.

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The amount of LIFO (last in first out) provision present at the reporting date when inventory is also valued using different valuation methods.

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- Definition

Other utility cost incurred related to store closures and other optimization costs produced and sold during the reporting period.

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