Impairment Of Long-Lived Assets (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010 item
Impaired Long-Lived Assets Held and Used [Line Items]
Provisions for impairment of long-lived assets	$ 764	$ 824	$ 15,161
Number of surplus properties			12
Building And Leasehold Improvements [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Provisions for impairment of long-lived assets			11,300
Property Leased To Franchisees [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Provisions for impairment of long-lived assets			2,300
Surplus Property [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Provisions for impairment of long-lived assets			$ 600