Debt (Carrying Value and Estimated Fair Value of Company's Long Term Debt) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
May 10, 2015	Aug. 31, 2014
Debt Instrument [Line Items]
Total long-term debt, carrying value	$ 6,026us-gaap_LongTermDebt	$ 5,093us-gaap_LongTermDebt
Less current portion, carrying value	1,200us-gaap_LongTermDebtCurrent	0us-gaap_LongTermDebtCurrent
Long-term debt, excluding current maturities	4,826us-gaap_LongTermDebtNoncurrent	5,093us-gaap_LongTermDebtNoncurrent
Total long-term debt, fair value	6,123us-gaap_LongTermDebtFairValue	5,217us-gaap_LongTermDebtFairValue
Less current portion, fair value	1,202	0
Long-term debt, excluding current portion, fair value	4,921cost_LongtermDebtFairValueNonCurrent	5,217cost_LongtermDebtFairValueNonCurrent
0.65% Senior Notes due December 2015
Debt Instrument [Line Items]
Debt instrument, stated interest rate (percent)	0.65%
Debt instrument, principal due date	2015-12
Total long-term debt, carrying value	1,200	1,199
Total long-term debt, fair value	1,202	1,203
5.5% Senior Notes due March 2017
Debt Instrument [Line Items]
Debt instrument, stated interest rate (percent)	5.50%
Debt instrument, principal due date	2017-03
Total long-term debt, carrying value	1,099	1,099
Total long-term debt, fair value	1,188	1,223
1.125% Senior Notes due December 2017
Debt Instrument [Line Items]
Debt instrument, stated interest rate (percent)	1.125%
Debt instrument, principal due date	2017-12
Total long-term debt, carrying value	1,100	1,100
Total long-term debt, fair value	1,102	1,095
1.7% Senior Notes due December 2019
Debt Instrument [Line Items]
Debt instrument, stated interest rate (percent)	1.70%
Debt instrument, principal due date	2019-12
Total long-term debt, carrying value	1,198	1,198
Total long-term debt, fair value	1,202	1,186
1.75% Senior Notes due February 2020
Debt Instrument [Line Items]
Debt instrument, stated interest rate (percent)	1.75%
Debt instrument, principal due date	2020-02
Total long-term debt, carrying value	499	0
Total long-term debt, fair value	497	0
2.25% Senior Notes due February 2022
Debt Instrument [Line Items]
Debt instrument, stated interest rate (percent)	2.25%
Debt instrument, principal due date	2022-02
Total long-term debt, carrying value	499	0
Total long-term debt, fair value	491	0
Other Long Term Debt
Debt Instrument [Line Items]
Total long-term debt, carrying value	431	497
Total long-term debt, fair value	$ 441	$ 510

The date when the principal portion of the notes is due to the holders.

No definition available.

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- Definition

Estimated fair value of the long-term debt current portion at the balance-sheet date.

+ References

No definition available.

+ Details

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- Definition

Estimated fair value of the non-current portion of long-term debt at the balance-sheet date.

+ References

No definition available.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Number 210

-Section 02

-Paragraph 20

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

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