Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 6,148	$ 6,209	$ 7,509
Charges to cost and expenses	688	334	(255)
Deductions	(2,377)	(395)	(1,045)
Balance at end of period	4,459	6,148	6,209
Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	589	855	455
Charges to cost and expenses	218	189	400
Deductions	(13)	(455)	0
Balance at end of period	$ 794	$ 589	$ 855