Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	Jul. 26, 2014	Jul. 27, 2013
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 265	$ 228
Preferred stock, par value (in dollars per share)	$ 0
Preferred stock, shares authorized (in shares)	5
Preferred stock, issued (in shares)	0
Preferred stock, outstanding (in shares)	0
Common stock, par value (in dollars per share)	$ 0.001
Common stock, shares authorized (in shares)	20,000
Common stock, shares issued (in shares)	5,107	5,389
Common stock, shares outstanding (in shares)	5,107	5,389