Short-term Borrowings and Long-term Debt (Schedule of Short-term Debt) (Details) (USD $) In Millions, unless otherwise specified	Jul. 28, 2013	Jul. 29, 2012
Short-term Debt [Line Items]
Commercial Paper	$ 1,162	$ 352
Notes Payable, Current	700	400
Variable rate bank borrowings	44	30
Capital Lease Obligations, Current	2	0
Other Short-term Borrowings	1	4
Debt, Current	$ 1,909	$ 786

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 within one year (or one operating cycle, if longer) of the balance sheet date.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

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Amount borrowed under the credit facility as of the balance sheet date.

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

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Sum of the carrying amounts at the balance sheet date of short-term borrowings not otherwise specified in the taxonomy having initial terms less than one year or the normal operating cycle, if longer.

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