Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Apr. 28, 2012	Jul. 30, 2011
Consolidated Balance Sheets [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 216	$ 204
Preferred stock, par value
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, issued	0	0
Preferred stock, outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	20,000,000,000	20,000,000,000
Common stock, shares issued	5,383,000,000	5,435,000,000
Common stock, shares outstanding	5,383,000,000	5,435,000,000