Acquisitions - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended	12 Months Ended
	Feb. 29, 2012	Nov. 30, 2011	Aug. 31, 2011	Feb. 29, 2012	May 31, 2012	Aug. 31, 2012	Aug. 24, 2011
Business Acquisition [Line Items]
Deposited into an escrow account for any post-closing adjustments						$ 500	$ 10,673
Acquired gross accounts receivable						972	542
Acquired gross accounts receivable not expected to be collected						430
Acquired gross accounts receivable resulting in fair value						542
Bargain purchase gain related to EMT	53		3,194	3,435
Acquisition-related transaction cost					55
Revenues from acquired assets					5,232
Income before income taxes from acquired assets					2,862
Increased bargain purchase gain	396	396
Deferred taxes, net	241	241
Estimated fair value of customer relationships acquired	140	140		140
Post closing adjustments, disbursed from the escrow funds	273	273
Determination of assets acquired and other components	$ 17	$ 17		$ 17