Condensed Consolidated Statements of Stockholders' Equity (USD $) In Millions, except Share data in Thousands, unless otherwise specified	Total USD ($)	Shares of Common Stock	Common Stock and Additional Paid In Capital USD ($)	Treasury Stock USD ($)	Accumulated Other Comprehensive Income USD ($)	Retained Earnings USD ($)
Beginning Balance at Jul. 31, 2011	$ 2,616		$ 2,886	$ (4,316)	$ 15	$ 4,031
Beginning Balance, shares at Jul. 31, 2011		300,597
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	54		0	0	0	54
Other comprehensive income (loss), net of income taxes	(6)		0	0	(6)	0
Comprehensive income	48
Issuance of treasury stock under employee stock plans	106		(39)	150	0	(5)
Issuance of treasury stock under employee stock plans, shares		5,590
Tax benefit from share-based compensation plans	45		45	0	0	0
Stock repurchases under stock repurchase programs	(586)		0	(586)	0	0
Stock repurchases under stock repurchase programs, shares	(11,400)	(11,411)
Cash dividends declared	(89)					(89)
Share-based compensation expense	83		83	0	0	0
Ending Balance at Jan. 31, 2012	2,223		2,975	(4,752)	9	3,991
Ending Balance, shares at Jan. 31, 2012		294,776
Beginning Balance at Jul. 31, 2012	2,744		3,018	(4,911)	25	4,612
Beginning Balance, shares at Jul. 31, 2012		295,289
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	52		0	0	0	52
Other comprehensive income (loss), net of income taxes	4		0	0	4	0
Comprehensive income	56
Issuance of treasury stock under employee stock plans	141		16	125	0	0
Issuance of treasury stock under employee stock plans, shares		4,814
Tax benefit from share-based compensation plans	56		56	0	0	0
Stock repurchases under stock repurchase programs	(200)		0	(200)	0	0
Stock repurchases under stock repurchase programs, shares	(3,400)	(3,361)
Cash dividends declared	(101)					(101)
Share-based compensation expense	96		96	0	0	0
Ending Balance at Jan. 31, 2013	$ 2,792		$ 3,186	$ (4,986)	$ 29	$ 4,563
Ending Balance, shares at Jan. 31, 2013		296,742