Share-Based Compensation Expense (Details 4) (Employee stock purchase plan ESPP [Member])	3 Months Ended	9 Months Ended
	Jul. 31, 2011	Jul. 31, 2011
Weighted average assumptions for option-based awards
Expected life (years)	0.5
Expected dividend yield	0.00%	0.00%
Minimum [Member]
Weighted average assumptions for option-based awards
Expected volatility	39.80%	39.80%
Risk-free interest rate, Minimum	0.19%	0.19%
Expected life (years)		0.25
Maximum [Member]
Weighted average assumptions for option-based awards
Expected volatility	48.40%	49.10%
Risk-free interest rate, Maximum	0.20%	0.64%
Expected life (years)		0.50