Significant Accounting Policies (Details)	3 Months Ended
	Jan. 31, 2015	Jan. 31, 2014
Significant Accounting Policies [Line Items]
Expected economic lives of finite-lived intangible assets, maximum (in years)	7 years
Expected number of years Spares usage cost is expensed (in years)	4 years
Percentage Of Revenue Recognized Using Percent-Of-Completion Method	1.00%	5.10%
One-time employee termination benefits related service period (more than 60 days)	60 days
4.0% Convertible Senior Notes due March 15, 2015
Significant Accounting Policies [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.00%
Maximum
Significant Accounting Policies [Line Items]
Measurement period for marketable debt securities (in years)	1 year
Derivative maturity (in months)	12 months
Maximum | Equipment, Furniture and Fixtures
Significant Accounting Policies [Line Items]
Estimated useful lives capitalized and amortized straight-line (in years)	5 years
Maximum | Software and Website Development
Significant Accounting Policies [Line Items]
Estimated useful lives capitalized and amortized straight-line (in years)	5 years
Minimum | Equipment, Furniture and Fixtures
Significant Accounting Policies [Line Items]
Estimated useful lives capitalized and amortized straight-line (in years)	2 years
Minimum | Software and Website Development
Significant Accounting Policies [Line Items]
Estimated useful lives capitalized and amortized straight-line (in years)	2 years