Segment Reporting (Details) $ in Millions	3 Months Ended
Nov. 30, 2016 USD ($) Segment	Nov. 30, 2015 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| Segment	3
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	$ 28,501	$ 29,033
Adjusted Operating Income	1,726	1,719
Acquisition-related amortization	(82)	(81)
Cost transformation	(81)	(90)
LIFO provision	(58)	(46)
Adjustments to equity earnings in AmerisourceBergen	(41)
Acquisition-related costs	(17)	(34)
Operating Income	1,447	1,468
Retail Pharmacy USA [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	20,659	20,370
Retail Pharmacy International [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	2,962	3,459
Pharmaceutical Wholesale [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	5,417	5,796
Reportable Segments [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	28,501	29,033
Reportable Segments [Member] \| Retail Pharmacy USA [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	20,659	20,370
Adjusted Operating Income	1,289	1,243
Reportable Segments [Member] \| Retail Pharmacy International [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	2,962	3,459
Adjusted Operating Income	213	315
Reportable Segments [Member] \| Pharmaceutical Wholesale [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	4,880	5,204
Adjusted Operating Income	224	166
Intersegment Eliminations [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	(537)	(592)
Adjusted Operating Income	0	(5)
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	0	0
Intersegment Eliminations [Member] \| Pharmaceutical Wholesale [Member]
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	$ 537	$ 592

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=66902209&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
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-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e1043-128460

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The change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods, which change has been reflected in the statement of income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6c)
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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
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-Section S99
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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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- Definition

This item represents the adjustments to equity earnings proportionate share for the period of the net income (loss) of AmerisourceBergen (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied.

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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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