Description of Business and Summary of Significant Accounting Policies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended			12 Months Ended	3 Months Ended
	Oct. 31, 2011	Oct. 31, 2010	Oct. 31, 2011 Accounts Receivable [Member] customers	Jul. 31, 2011 Accounts Receivable [Member] customers	Oct. 31, 2011 Sales [Member] customers	Oct. 31, 2010 Sales [Member] customers
Numerator:
Net loss	$ (64)	$ (70)
Shares used in diluted per share amounts:
Weighted average common shares outstanding	300	316
Basic and diluted net loss per share:
Basic net loss per share	$ (0.21)	$ (0.22)
Diluted net loss per share	$ (0.21)	$ (0.22)
Weighted average stock options and restricted stock units that would have been included in the computation of diluted common equivalent shares outstanding if net income had been reported in the period	28	33
Weighted average stock options and restricted stock units excluded from calculation due to anti-dilutive effect	3	5
Number of customers accounted for more than ten percent of concentration risk			0	0	0	0