Accrued Liabilities (Details) (USD $) In Thousands	Aug. 31, 2011	Aug. 31, 2010
Accrued liabilities [Abstract]
Securities class action liability	$ 161,150	$ 177,982
Salaries, wages and benefits	93,763	80,773
Accrued advertising	50,172	52,472
Accrued professional fees	32,607	30,895
Student refunds, grants and scholarships	17,360	9,842
Other accrued liabilities	43,754	23,497
Total accrued liabilities	$ 398,806	$ 375,461