Notes Payable and Long-Term Debt - Schedule of Long-Term Debt Payable (Details) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012	Aug. 31, 2011
Debt Disclosure [Abstract]
Long-term Debt, Repayments in 2013	$ 108,211
Long-term Debt, Repayments in 2014	161,986
Long-term Debt, Repayments in 2015	163,647
Long-term Debt, Repayments in 2016	130,044
Long-term Debt, Repayments in 2017	150,213
Long-term Debt, Repayments after 2017	726,252
Total long-term debt	$ 1,440,353	$ 1,501,997

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

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