Fair Value (Additional Information) (Details) (USD $)							3 Months Ended
	Oct. 25, 2014	Jul. 26, 2014	Oct. 25, 2014 Level 2	Jul. 26, 2014 Level 2	Oct. 25, 2014 Level 3	Jul. 26, 2014 Level 3	Oct. 25, 2014 Level 3 Investments In Privately Held Companies [Member]	Oct. 26, 2013 Level 3 Investments In Privately Held Companies [Member]
Fair Value Measurements [Line Items]
Private investment impairment							$ 1,000,000	$ 1,000,000
Carrying Value, Cost Method Investments	327,000,000	269,000,000
Long term loan receivables and financed service contracts and others carrying value					1,900,000,000	2,100,000,000
Senior notes, fair value			22,400,000,000	22,400,000,000
Senior notes, carrying value	$ 20,965,000,000	$ 20,901,000,000	$ 21,000,000,000	$ 20,900,000,000