Accounts And Notes Receivable (Schedule Of Accounts And Notes Receivable) (Details) - USD ($) $ in Thousands	Aug. 31, 2017	Aug. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Royalties and other trade receivables	$ 19,571	$ 19,994
Current accounts and notes receivable, gross	34,847	36,404
Allowance for doubtful accounts and notes receivable	(1,089)	(967)
Current accounts and notes receivable, net	33,758	35,437
Allowance for doubtful notes receivable	(42)	(74)
Noncurrent notes receivable, net	9,801	12,562
Notes Receivable From Franchisees [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current accounts and notes receivable, gross	1,441	5,531
Noncurrent notes receivable, gross	6,810	7,170
Receivables From System Funds [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current accounts and notes receivable, gross	6,360	4,372
Noncurrent notes receivable, gross	3,033	5,466
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current accounts and notes receivable, gross	$ 7,475	$ 6,507