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	(170)				(20)	(150)
Issuance of stock under employee stock plans, shares		3,463
Issuance of stock under employee stock plans	$ 101		101
Stock repurchases under stock repurchase programs, shares	(7,500)	(7,473)
Stock repurchases under stock repurchase programs	$ (668)			(668)
Dividends and dividend rights declared	(147)					(147)
Tax benefit from share-based compensation plans	38		38
Share-based compensation expense	122		122
Ending Balance, shares at Jan. 31, 2015		280,940
Ending Balance at Jan. 31, 2015	2,354		3,822	(7,098)	(22)	5,652
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	(19)				(12)	(7)
Issuance of stock under employee stock plans, shares		1,901
Issuance of stock under employee stock plans	$ 56		56
Stock repurchases under stock repurchase programs, shares	(19,100)	(19,134)
Stock repurchases under stock repurchase programs	$ (1,725)			(1,725)
Dividends and dividend rights declared	(163)					(163)
Tax benefit from share-based compensation plans	20		20
Share-based compensation expense	140		140
Ending Balance, shares at Jan. 31, 2016		260,473
Ending Balance at Jan. 31, 2016	$ 641		$ 4,226	$ (9,400)	$ (42)	$ 5,857