Segment Reporting (Details) $ in Millions	3 Months Ended	6 Months Ended
Feb. 28, 2017 USD ($)	Feb. 29, 2016 USD ($)	Feb. 28, 2017 USD ($) segment	Feb. 29, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			3
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	$ 29,446	$ 30,184	$ 57,947	$ 59,217
Adjusted Operating Income	2,016	2,120	3,742	3,839
Cost transformation	(340)	(28)	(421)	(118)
Acquisition-related amortization	(82)	(101)	(164)	(182)
LIFO provision	(49)	(68)	(107)	(114)
Adjustments to equity earnings in AmerisourceBergen	(37)		(78)
Acquisition-related costs	(29)	(33)	(46)	(67)
Asset impairment		(30)		(30)
Operating Income	1,479	1,860	2,926	3,328
Retail Pharmacy USA
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	21,814	21,500	42,473	41,870
Adjusted Operating Income	1,552	1,632	2,841	2,875
Retail Pharmacy International
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	3,101	3,627	6,063	7,086
Adjusted Operating Income	242	335	455	650
Pharmaceutical Wholesale
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	4,531	5,057	9,411	10,261
Adjusted Operating Income	226	155	450	321
Reportable Segments
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	29,446	30,184	57,947	59,217
Reportable Segments \| Retail Pharmacy USA
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	21,814	21,500	42,473	41,870
Adjusted Operating Income	1,552	1,632	2,841	2,875
Reportable Segments \| Retail Pharmacy International
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	3,101	3,628	6,063	7,087
Adjusted Operating Income	242	335	455	650
Reportable Segments \| Pharmaceutical Wholesale
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	5,030	5,627	10,447	11,423
Adjusted Operating Income	226	155	450	321
Eliminations
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	(499)	(571)	(1,036)	(1,163)
Adjusted Operating Income	(4)	(2)	(4)	(7)
Eliminations \| Retail Pharmacy USA
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	0	0	0	0
Eliminations \| Retail Pharmacy International
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	0	1	0	1
Eliminations \| Pharmaceutical Wholesale
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	$ 499	$ 570	$ 1,036	$ 1,162

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.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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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.

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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.

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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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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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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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