Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	Total USD ($)	Shares of Common Stock [Member]	Common Stock and Additional Paid In Capital [Member] USD ($)	Treasury Stock [Member] USD ($)	Accumulated Other Comprehensive Loss [Member] USD ($)	Retained Earnings [Member] USD ($)
Beginning Balance at Jul. 31, 2013	$ 3,531		$ 3,201	$ (4,952)	$ 20	$ 5,262
Beginning Balance, shares at Jul. 31, 2013		299,503
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	928				(8)	936
Issuance of stock under employee stock plans, shares		5,267
Issuance of stock under employee stock plans	169		70	99
Stock repurchases under stock repurchase programs, shares	(20,500)	(20,507)
Stock repurchases under stock repurchase programs	(1,425)			(1,425)
Dividends and dividend rights declared	(165)					(165)
Tax benefit from share-based compensation plans	52		52
Share-based compensation expense	148		148
Ending Balance at Apr. 30, 2014	3,238		3,471	(6,278)	12	6,033
Ending Balance, shares at Apr. 30, 2014		284,263
Beginning Balance at Jul. 31, 2014	3,078		3,561	(6,430)	(2)	5,949
Beginning Balance, shares at Jul. 31, 2014		284,950
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	333				(18)	351
Issuance of stock under employee stock plans, shares		4,431
Issuance of stock under employee stock plans	129		129
Stock repurchases under stock repurchase programs, shares	(13,700)	(13,723)
Stock repurchases under stock repurchase programs	(1,236)			(1,236)
Dividends and dividend rights declared	(218)					(218)
Tax benefit from share-based compensation plans	51		51
Share-based compensation expense	184		184
Ending Balance at Apr. 30, 2015	$ 2,321		$ 3,925	$ (7,666)	$ (20)	$ 6,082
Ending Balance, shares at Apr. 30, 2015		275,658