Maintenance and Warranty Accruals (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Accrued maintenance
Balance at beginning of period	$ 10,865	$ 12,460	$ 16,206
Charged to cost of revenue	10,750	12,034	13,581
Payments	(10,140)	(13,629)	(17,327)
Balance at end of period	11,475	10,865	12,460
Accrued warranty
Balance at beginning of period	8,645	6,304	8,184
Charged to cost of revenue	2,496	3,856	425
Payments	(1,746)	(1,547)	(2,252)
Currency translation effect	(174)	32	(53)
Balance at end of period	$ 9,221	$ 8,645	$ 6,304