Short-term Borrowings and Long-term Debt Short-term Borrowings and Long-term Debt (Schedule of Long-term Debt Instruments) (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 02, 2015	Aug. 03, 2014
Debt Instrument [Line Items]
Long-term Debt	$ 2,552	$ 2,544
Capital Lease Obligations, Noncurrent	10	3
Debt Instrument, Unamortized Discount (Premium), Net	8	9
Long Term Debt And Capital Lease Obligations Aggregate	2,552	2,544
Long-term Debt, Current Maturities	0	300
Long-term Debt and Capital Lease Obligations	2,552	$ 2,244
3.38% notes, due 2015
Debt Instrument [Line Items]
Debt Instrument, Maturity Date		Aug. 15, 2014
Debt Instrument, Interest Rate, Stated Percentage		3.38%
Long-term Debt	$ 0	$ 300
3.05% notes, due 2017
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jul. 15, 2017
Debt Instrument, Interest Rate, Stated Percentage	3.05%	3.05%
Long-term Debt	$ 400	$ 400
4.50% notes, due 2019
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Feb. 15, 2019
Debt Instrument, Interest Rate, Stated Percentage	4.50%	4.50%
Long-term Debt	$ 300	$ 300
4.25% notes, due 2021
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Apr. 15, 2021
Debt Instrument, Interest Rate, Stated Percentage	4.25%	4.25%
Long-term Debt	$ 500	$ 500
8.88% notes, due 2021
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	May 01, 2021
Debt Instrument, Interest Rate, Stated Percentage	8.88%	8.88%
Long-term Debt	$ 200	$ 200
2.50% notes, due 2023
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Aug. 02, 2022
Debt Instrument, Interest Rate, Stated Percentage	2.50%	2.50%
Long-term Debt	$ 450	$ 450
3.30% notes, due 2025
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Mar. 19, 2025
Debt Instrument, Interest Rate, Stated Percentage	3.30%
Long-term Debt	$ 300	$ 0
3.80% notes, due 2043
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Aug. 02, 2042
Debt Instrument, Interest Rate, Stated Percentage	3.80%	3.80%
Long-term Debt	$ 400	$ 400

Long Term Debt And Capital Lease Obligations Aggregate. Includes the current portion of debt.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

+ References

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- Definition

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

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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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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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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.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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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.

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