Long-Term Obligations and Commitments (Details) (USD $)	1 Months Ended	12 Months Ended
	May 31, 2009	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012	Mar. 12, 2007
Long Term Obligations And Commitments (Textuals)
Senior notes					$ 1,000,000,000
Interest paid		32,000,000	33,000,000	60,000,000
Cash paid to license technology	20,000,000	15,000,000	14,000,000	10,000,000
Amount payable over next ten fiscal years for agreement to license technology	100,000,000
Present value of license technology agreement	89,000,000
Years lease term can be extended under lease option		10 years
Operating leases, rent expense		57,000,000	53,000,000	47,000,000
Other long-term obligations
Total deferred rent		62,000,000	55,000,000
Total license fee payable		41,000,000	48,000,000
Long-term income tax liabilities		32,000,000	38,000,000
Long-term deferred revenue		10,000,000	32,000,000
Long-term deferred income tax liabilities		61,000,000	6,000,000
Other		14,000,000	7,000,000
Total long-term obligations		220,000,000	186,000,000
Less current portion (included in other current liabilities)		(17,000,000)	(19,000,000)
Long-term obligations due after one year		203,000,000	167,000,000
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating Leases, Future Minimum Payments Due, Current		72,000,000
Operating Leases, Future Minimum Payments, Due in Two Years		69,000,000
Operating Leases, Future Minimum Payments, Due in Three Years		69,000,000
Operating Leases, Future Minimum Payments, Due in Four Years		55,000,000
Operating Leases, Future Minimum Payments, Due in Five Years		45,000,000
Operating Leases, Future Minimum Payments, Due Thereafter		260,000,000
Operating Leases, Future Minimum Payments Due		570,000,000
Senior Notes [Member]
Long Term Obligations And Commitments (Textuals)
Interest paid		29,000,000	29,000,000	56,000,000
5.40% fixed-rate notes, due 2012 [Member]
Long Term Obligations And Commitments (Textuals)
Senior notes					500,000,000
Senior notes, rate					5.40%
5.75% fixed-rate notes, due 2017 [Member]
Long Term Obligations And Commitments (Textuals)
Senior notes					500,000,000
Senior notes, rate					5.75%
Purchase Commitment [Member]
Purchase Obligation, Fiscal Year Maturity [Abstract]
Purchase Obligation, Due in Next Twelve Months		30,000,000
Purchase Obligation, Due in Second Year		18,000,000
Purchase Obligation, Due in Third Year		10,000,000
Purchase Obligation, Due in Fourth Year		61,000,000
Purchase Obligation, Due in Fifth Year		0
Purchase Obligation, Due after Fifth Year		1,000,000
Purchase Obligation		$ 120,000,000