Debt - Short and Long-Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
May 31, 2019	Aug. 31, 2018
Debt Instrument [Line Items]
Total short-term debt	$ 5,483	$ 1,966
Credit facilities	996	0
Other	25	23
Total long-term debt, less current portion	12,127	12,431
Other short term debt
Debt Instrument [Line Items]
Total short-term debt	465	288
Unsecured notes \| 2.700% unsecured notes due 2019
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 0	1,248
Stated interest rate	2.70%
Maturity year	2019
Unsecured notes \| 3.450% unsecured notes due 2026
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 1,889	1,888
Stated interest rate	3.45%
Maturity year	2026
Unsecured notes \| 4.650% unsecured notes due 2046
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 591	590
Stated interest rate	4.65%
Maturity year	2046
Unsecured notes \| 3.300% unsecured notes due 2021
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 1,246	1,245
Stated interest rate	3.30%
Maturity year	2021
Unsecured notes \| 3.800% unsecured notes due 2024
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 1,991	1,990
Stated interest rate	3.80%
Maturity year	2024
Unsecured notes \| 4.500% unsecured notes due 2034
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 495	495
Stated interest rate	4.50%
Maturity year	2034
Unsecured notes \| 4.800% unsecured notes due 2044
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 1,492	1,492
Stated interest rate	4.80%
Maturity year	2044
Unsecured notes \| 2.875% unsecured Pound sterling notes due 2020
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 503	517
Stated interest rate	2.875%
Maturity year	2020
Unsecured notes \| 3.600% unsecured Pound sterling notes due 2025
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 376	387
Stated interest rate	3.60%
Maturity year	2025
Unsecured notes \| 2.125% unsecured Euro notes due 2026
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 833	868
Stated interest rate	2.125%
Maturity year	2026
Unsecured notes \| 3.100% unsecured notes due 2022
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 1,197	1,196
Stated interest rate	3.10%
Maturity year	2022
Unsecured notes \| 4.400% unsecured notes due 2042
Debt Instrument [Line Items]
Carrying value of notes, net of unamortized discount and interest rate swap FMV adjustment	$ 493	492
Stated interest rate	4.40%
Maturity year	2042
Commercial paper
Debt Instrument [Line Items]
Total short-term debt	$ 2,820	430
Credit facilities
Debt Instrument [Line Items]
Total short-term debt	948	999
Notes payable \| 2.700% unsecured notes due 2019
Debt Instrument [Line Items]
Total short-term debt	$ 1,249	0
Stated interest rate	2.70%
Maturity year	2019
Notes payable \| 5.250% unsecured notes due 2019
Debt Instrument [Line Items]
Total short-term debt	$ 0	$ 249
Stated interest rate	5.25%
Maturity year	2019

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

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.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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- Definition

Amount of long-term debt classified as other.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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- Definition

Year when the debt instrument is scheduled to be fully repaid.

+ References

No definition available.

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- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums and unamortized fair market value adjustments, if any.

+ References

No definition available.

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