Fair value portion of investments accounted under the equity method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 25
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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

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(12))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Number of shares of affiliates held for management investment companies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
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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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This item represents the carrying amount exceeded its proportionate share of the net assets of an equity method investee.

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No definition available.

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Percentage of outstanding common shares of affiliates held for management investment companies.

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Period of reporting lag for availability of financial information.

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Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended
Equity Method Investments (Details) - USD ($) $ in Millions	Nov. 30, 2016	Nov. 30, 2015	Aug. 31, 2016
Schedule of Equity Method Investments [Line Items]
Equity earnings	$ 12	$ 11
AmerisourceBergen [Member]
Schedule of Equity Method Investments [Line Items]
Outstanding shares owned (in shares)	56,854,867		56,854,867
Percentage of outstanding common shares owned	26.00%		24.00%
Period of reporting lag	2 months
Equity investment, exceeded its proportionate share of net assets	$ 4,400
AmerisourceBergen [Member] \| Level 1 [Member]
Schedule of Equity Method Investments [Line Items]
Fair market value of equity investment	4,400
Other Investments [Member]
Schedule of Equity Method Investments [Line Items]
Equity earnings	$ 12	$ 11