Supplementary Financial Information, Assets and Liabilities Included in Consolidated Balance Sheet Captions (Details) - USD ($) $ in Millions	Aug. 31, 2016	Aug. 31, 2015	Aug. 31, 2014
Accounts receivable [Abstract]
Accounts receivable	$ 6,426	$ 7,021
Allowance for doubtful accounts	(166)	(172)	$ (173)
Net, Total	6,260	6,849
Other non-current assets [Abstract]
Investment in AmerisourceBergen	0	1,147
Warrants	0	2,140
Other	467	805
Other non-current assets, Total	467	4,092
Accrued expenses and other liabilities [Abstract]
Accrued salaries and wages	1,398	1,357
Other	4,086	3,868
Accrued expenses and other liabilities, Total	$ 5,484	$ 5,225

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Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of the obligations incurred through that date and payable for employees' services provided. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Amount of assets classified as other.

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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Fair value of investment in AmerisourceBergen.

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Fair values as of the balance sheet date of all warrant assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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