Commitments and Contingencies (Details) (Ontario Grant [Member], CAD) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Apr. 30, 2012	Apr. 30, 2012
Ontario Grant [Member]
Gain Contingencies [Line Items]
Grant amount	25.0
Grant period	November 1, 2010 to October 31, 2015
Annual disbursements	5.0
Benefit recorded to date	8.3	3.0
Grant amount received in fiscal 2011	5.0