Fair Value (Additional Information) (Details) - USD ($) $ in Millions	Jul. 30, 2016	Jul. 25, 2015
Fair Value Measurements [Line Items]
Carrying Value, Cost Method Investments	$ 829	$ 727
Senior notes, carrying value	28,642	25,351
Level 2
Fair Value Measurements [Line Items]
Senior notes, fair value	30,900	26,600
Level 3
Fair Value Measurements [Line Items]
Long term loan receivables and financed service contracts and others carrying value	2,600	$ 2,200
Investments In Privately Held Companies | Level 3
Fair Value Measurements [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	24
Purchased Intangible Assets | Level 3
Fair Value Measurements [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 0