Settlement Of Contingency - Additional Information (Detail)	3 Months Ended				9 Months Ended
	Jul. 27, 2012 USD ($)	Apr. 27, 2012 USD ($)	Apr. 27, 2012 CAD	Jul. 29, 2011 USD ($)	Jul. 27, 2012 USD ($)	Jul. 29, 2011 USD ($)
Contingent Liabilities [Line Items]
Gain on settlement of contingency	$ 0	$ 11,900,000	11,800,000	$ 0	$ 11,891,000	$ 0
Gain on settlement of contingency after tax		$ 9,500,000