Earnings (Loss) Per Share Calculation (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2014	Jul. 31, 2013
Numerator
Net income (loss)	$ 16,160	$ (1,231)	$ (9,934)	$ (75,634)
Add: Interest expense associated with 0.875% convertible senior notes due 2017	1,384	0	0	0
Net income (loss) used to calculate Diluted EPS	$ 17,544	$ (1,231)	$ (9,934)	$ (75,634)
Denominator
Weighted average basic common shares outstanding	106,236	102,713	105,404	101,951
Add: Shares underlying outstanding stock options, employees stock purchase plan and restricted stock units	1,465	0	0	0
Add: Shares underlying 0.875% convertible senior notes due 2017	13,108	0	0	0
Weighted average dilutive potential common shares outstanding	120,809	102,713	105,404	101,951
EPS
Basic EPS (in dollars per share)	$ 0.15	$ (0.01)	$ (0.09)	$ (0.74)
Diluted EPS (in dollars per share)	$ 0.15	$ (0.01)	$ (0.09)	$ (0.74)