Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 26, 2014	Jul. 27, 2013	Jul. 28, 2012
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax	$ (146)	$ (2)	$ 6
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax	111	17	36
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax	0	(1)	0
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax	$ (5)	$ (1)	$ 36