Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jan. 31, 2012
Loss Contingencies [Line Items]
Maximum amount of reasonably possible losses	$ 13.2
Loss contingency amount accrued for probable losses	5.4
Restitution paid	0.1
Augustus
Loss Contingencies [Line Items]
Break claim which seeks damages	103.0
Final hearing date	Apr. 23, 2012
Diaz | Settlement of Litigation
Loss Contingencies [Line Items]
Final hearing date	May 21, 2012
Maximum amount of reasonably possible losses	4.7
Anticipated payment for settlement of case	2.9
Loss contingency amount accrued for probable losses	$ 2.9
Simpson
Loss Contingencies [Line Items]
Final hearing date	Feb. 11, 2013
Khadera
Loss Contingencies [Line Items]
Final hearing date	Apr. 02, 2012