Goodwill and Purchased Intangible Assets (Additional Information) (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended		12 Months Ended
	Jan. 23, 2016	Jan. 24, 2015	Oct. 25, 2014	Jan. 23, 2016	Jan. 24, 2015	Jul. 25, 2015
Finite-Lived Intangible Assets [Line Items]
Impairment	$ 37	$ 56		$ 37	$ 56
Cost of Goods Sold	$ 3,480	$ 3,806		$ 7,333	$ 7,725
Rockstar Consortium
Finite-Lived Intangible Assets [Line Items]
Settlement of Patent Infringement Claims (Include capitalized and expensed portion)						$ 300
Cost of Goods Sold			$ 188