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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Fair value portion of investments accounted under the equity method.

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Number of shares of affiliates held for management investment companies.

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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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Equity method investments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Nov. 30, 2018	Nov. 30, 2017	Aug. 31, 2018
Schedule of Equity Method Investments [Line Items]
Equity earnings (losses)	$ 54	$ (99)
AmerisourceBergen
Schedule of Equity Method Investments [Line Items]
Outstanding shares owned (in shares)	56,854,867		56,854,867
Ownership percentage	27.00%		26.00%
Period of reporting lag	2 months
Equity investment, exceeded its proportionate share of net assets	$ 4,400
AmerisourceBergen \| Level 1
Schedule of Equity Method Investments [Line Items]
Fair market value of equity investment	5,100
Other Investments
Schedule of Equity Method Investments [Line Items]
Equity earnings (losses)	$ 15	$ 13