Leases (Schedule Of Future Minimum Rental Payments) (Details) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012	Aug. 31, 2011
Leases [Abstract]
Operating, 2013	$ 11,877
Operating, 2014	11,783
Operating, 2015	11,668
Operating, 2016	11,123
Operating, 2017	10,098
Operating, Thereafter	104,337
Operating, Total minimum lease payments	160,886
Capital, 2013	5,845
Capital, 2014	6,172
Capital, 2015	5,312
Capital, 2016	4,876
Capital, 2017	4,471
Capital, Thereafter	14,620
Capital, Total minimum lease payments	41,296
Capital, Less amount representing interest averaging 6.6%	(9,620)
Capital, Present value of net minimum lease payments	31,676
Less amount due within one year	(4,299)
Capital, Amount due after one year	$ 27,377	$ 30,302
Capital, Average interest rate	6.60%

Percentage of imputed average capital lease interest

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid within one year (or one operating cycle, if longer) of the balance sheet date.

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Amount of minimum lease payments maturing in the fifth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the third fiscal year following the latest fiscal year for capital leases.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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