Sale of Elk Grove Village Building - Additional Information (Detail) (USD $)	6 Months Ended	9 Months Ended
	Aug. 31, 2012	Nov. 30, 2012 sqft	Jul. 23, 2012 sqft
Discontinued Operations [Line Items]
Facility leased to Main Steel Polishing Company, Inc.			240,000
Leasable area of facility			280,000
Proceeds from sale of assets	$ 9,200,000	$ 9,180,000
Gain on sales of assets	3,200,000	3,216,000
Tax loss on sale of assets	5,400,000
Expected tax savings due to tax loss	$ 1,800,000
Lease agreement with Torburn		35,000
Lease term		4 years