Rollforward of Accrued Product Warranty Reserve (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	May 31, 2014	May 31, 2013
Movement in Standard Product Warranty Accrual [Roll Forward]
Beginning balance	$ 7,413	$ 5,121
Provision for warranties	2,923	5,093
Warranty reserve of acquired business	50	0
Warranty payments and costs incurred	(5,311)	(4,931)
Impact of changes in foreign currency rates	30	32
Ending balance	$ 5,105	$ 5,315