Borrowings (Additional Information) (Details) (USD $)	3 Months Ended							3 Months Ended		3 Months Ended
	Oct. 25, 2014	Oct. 26, 2013	Jul. 26, 2014	Oct. 25, 2014 Derivatives designated as hedging instruments: Interest rate derivatives	Jul. 26, 2014 Derivatives designated as hedging instruments: Interest rate derivatives	Oct. 25, 2014 Fixed-Rate Notes, 2.90%, Due November 2014	Jul. 26, 2014 Fixed-Rate Notes, 2.90%, Due November 2014	Oct. 25, 2014 Unsecured revolving credit facility	Oct. 25, 2014 Maximum	Jan. 24, 2015 Subsequent Event Fixed-Rate Notes, 2.90%, Due November 2014
Debt Instrument [Line Items]
Commercial paper	$ 0		$ 0						$ 3,000,000,000
Repayments of Senior Debt	3,000,000	0								500,000,000
Senior Notes						500,000,000	500,000,000
Derivative, Notional Amount	16,507,000,000		15,557,000,000	10,400,000,000	10,400,000,000
Line of Credit Facility, Current Borrowing Capacity								3,000,000,000
Maturity date								Feb. 17, 2017
Interest Rate-Federal Funds rate plus 0.50%								0.50%
Interest rate-one-month LIBOR plus 1.00%								1.00%
Line of Credit Facility, Interest Rate Description								Any advances under the credit agreement will accrue interest at rates that are equal to, based on certain conditions, either (i) the higher of the Federal Funds rate plus 0.50%, Bank of America’s “prime rate” as announced from time to time, or one-month LIBOR plus 1.00% or (ii) LIBOR plus a margin that is based on the Company’s senior debt credit ratings as published by Standard & Poor’s Financial Services, LLC and Moody’s Investors Service, Inc.
Additional credit facility upon agreement								$ 2,000,000,000
Additional unsecured revolving credit facility maturity date								Feb. 17, 2019