Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (USD $) In Millions, except Share data, unless otherwise specified	Total	Common Stock [Member]	Common Stock and Additional Paid In Capital	Treasury Stock	Accumulated Other Comprehensive Income	Retained Earnings
Beginning Balance at Jul. 31, 2010	$ 2,821		$ 2,728	$ (3,315)	$ 11	$ 3,397
Beginning Balance, shares at Jul. 31, 2010		313,861,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	3	0	0	0	0	3
Other comprehensive income (loss), net of tax	0	0	0	0	0	0
Comprehensive net income (loss)	3
Issuance of treasury stock under employee stock plans	187		(29)	216	0	0
Issuance of treasury stock under employee stock plans, shares		9,583,000
Stock repurchases under stock repurchase programs	(860)		0	(860)	0	0
Stock repurchases under stock repurchase programs, shares	(18,500,000)	(18,459,000)
Tax benefit from share-based compensation plans	48	0	48	0	0	0
Share-based compensation expense	73	0	73	0	0	0
Ending Balance at Jan. 31, 2011	2,272		2,820	(3,959)	11	3,400
Ending Balance, shares at Jan. 31, 2011		304,985,000
Beginning Balance at Jul. 31, 2011	2,616		2,886	(4,316)	15	4,031
Beginning Balance, shares at Jul. 31, 2011		300,597,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	54	0	0	0	0	54
Other comprehensive income (loss), net of tax	(6)	0	0	0	(6)	0
Comprehensive net income (loss)	48
Issuance of treasury stock under employee stock plans	106		(39)	150	0	(5)
Issuance of treasury stock under employee stock plans, shares		5,590,000
Stock repurchases under stock repurchase programs	(586)		0	(586)	0	0
Cash dividends declared ($0.30 per share)	(89)					(89)
Stock repurchases under stock repurchase programs, shares	(11,400,000)	(11,411,000)
Tax benefit from share-based compensation plans	45	0	45	0	0	0
Share-based compensation expense	83	0	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		294,776,000