Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Millions	Total	Shares of Common Stock	Common Stock and Additional Paid-In Capital	Treasury Stock	Accumulated Other Comprehensive Loss	Retained Earnings
Beginning Balance, shares at Jul. 31, 2014		284,950
Beginning Balance at Jul. 31, 2014	$ 3,078		$ 3,561	$ (6,430)	$ (2)	$ 5,949
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive loss	(89)				(5)	(84)
Issuance of stock under employee stock plans, shares		1,787
Issuance of stock under employee stock plans	$ 47		47
Stock repurchases under stock repurchase programs, shares	(1,300)	(1,318)
Stock repurchases under stock repurchase programs	$ (114)			(114)
Dividends and dividend rights declared	(74)					(74)
Tax benefit from share-based compensation plans	18		18
Share-based compensation expense	61		61
Ending Balance, shares at Oct. 31, 2014		285,419
Ending Balance at Oct. 31, 2014	2,927		3,687	(6,544)	(7)	5,791
Beginning Balance, shares at Jul. 31, 2015		277,706
Beginning Balance at Jul. 31, 2015	2,332		4,010	(7,675)	(30)	6,027
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive loss	(33)				(2)	(31)
Issuance of stock under employee stock plans, shares		998
Issuance of stock under employee stock plans	$ 24		24
Stock repurchases under stock repurchase programs, shares	(14,400)	(14,359)
Stock repurchases under stock repurchase programs	$ (1,270)			(1,270)
Dividends and dividend rights declared	(82)					(82)
Tax benefit from share-based compensation plans	9		9
Share-based compensation expense	71		71
Ending Balance, shares at Oct. 31, 2015		264,345
Ending Balance at Oct. 31, 2015	$ 1,051		$ 4,114	$ (8,945)	$ (32)	$ 5,914