Shareholders' Equity (Stock Repurchase Program) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended
	Apr. 26, 2014
Stock Repurchase Program [Roll Forward]
Cumulative shares repurchased, beginning balance	3,868
Repurchase of common stock under the stock repurchase program (1)	359	[1]
Cumulative shares repurchased, ending balance	4,227
Cumulative weighted-average price per share, beginning balance	$ 20.40
Weighted Average Price Per Share Of Stock Repurchased In Period	$ 22.31
Cumulative weighted-average price per share, ending balance	$ 20.56
Cumulative amount repurchased, beginning balance	$ 78,906
Repurchase of common stock under the stock repurchase program, amount	8,025	[1]
Cumulative amount repurchased, ending balance	$ 86,931

[1] Includes stock repurchases of $60 million, which were pending settlement as of April 26, 2014. There were no stock repurchases pending settlement as of July 27, 2013.