Goodwill and Other Intangible Assets - Carrying Amount and Accumulated Amortization of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Goodwill And Other Intangible Assets [Line Items]
Carrying Amount	$ 2,038	$ 2,038
Accumulated Amortization	1,725	1,571
Patents [Member]
Goodwill And Other Intangible Assets [Line Items]
Carrying Amount	1,748	1,748
Accumulated Amortization	1,538	1,500
Customer Lists [Member]
Goodwill And Other Intangible Assets [Line Items]
Carrying Amount	190	190
Accumulated Amortization	154	59
Non-Compete Agreements [Member]
Goodwill And Other Intangible Assets [Line Items]
Carrying Amount	100	100
Accumulated Amortization	$ 33	$ 12