Long-Term Obligations and Commitments - Other Long-Term Obligations (Details) - USD ($) $ in Millions	1 Months Ended
	May 31, 2009	Jul. 31, 2017	Jul. 31, 2016
Long-Term Obligations and Commitments [Abstract]
Total deferred rent		$ 49	$ 56
Long-term income tax liabilities		53	54
Total license fee payable		18	26
Long-term deferred income tax liabilities		7	7
Other		20	20
Total long-term obligations		147	163
Less current portion (included in other current liabilities)		(17)	(17)
Long-term obligations due after one year		$ 130	$ 146
Long Term Obligations and Commitments (Textuals) [Abstract]
Cash paid to license technology	$ 20
Amount payable over next ten fiscal years for agreement to license technology	$ 100
Operating lease, term	10 years
Present value of license technology agreement	$ 89