Long-Term Obligations (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended				3 Months Ended
	Apr. 30, 2011	Apr. 30, 2010	Jul. 31, 2010	Mar. 12, 2007	Apr. 30, 2011 5.40% fixed-rate notes, due 2012 [Member]	Mar. 12, 2007 5.40% fixed-rate notes, due 2012 [Member]	Mar. 12, 2007 5.75% fixed-rate notes, due 2017 [Member]
Long Term Obligations (Textuals)
Senior notes				$ 1,000		$ 500	$ 500
Period for contractual maturities of senior notes					within 1 year
Unamortized discounts on senior notes	2		2
Senior notes, rate						5.40%	5.75%
Cash paid for interest on the Notes	56	56
Other long-term obligations
Total license fee payable	69		65
Total deferred rent	53		60
Long-term deferred revenue	39		29
Long-term income tax liabilities	40		20
Long-term payables	19		0
Other	2		3
Total long-term obligations	222		177
Less current portion (included in other current liabilities)	(18)		(19)
Long-term obligations due after one year	$ 204		$ 158