Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2016	Jan. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 24	$ (66)	$ (7)	$ (150)
Other comprehensive loss, net of income taxes:
Foreign currency translation losses	(10)	(15)	(12)	(20)
Total other comprehensive income (loss), net	(10)	(15)	(12)	(20)
Comprehensive income (loss)	$ 14	$ (81)	$ (19)	$ (170)