Restructuring and Other Expense (Income) - Additional Information (Detail) (USD $)	3 Months Ended
	Aug. 31, 2013	May 31, 2013
Restructuring Cost and Reserve [Line Items]
Future payments for restructuring	$ 4,794,000
ITS
Restructuring Cost and Reserve [Line Items]
Cash proceeds from sale of assets for sale assets	7,457,000
Gain on asset disposals	4,762,000
Metal Framing
Restructuring Cost and Reserve [Line Items]
Facility exit and other costs incurred	142,000
Commercial Stairs
Restructuring Cost and Reserve [Line Items]
Facility exit and other costs incurred	363,000
Pressure Cylinders
Restructuring Cost and Reserve [Line Items]
Severance accrual adjustment	$ 402,000	$ 2,488,000