Accounts And Notes Receivable (Details) - USD ($) $ in Thousands	May 31, 2018	Aug. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Royalties and other trade receivables	$ 21,046	$ 19,571
Current accounts and notes receivable, gross	38,672	34,847
Allowance for doubtful accounts and notes receivable	(1,101)	(1,089)
Current accounts and notes receivable, net	37,571	33,758
Allowance for doubtful notes receivable	(437)	(42)
Noncurrent notes receivable, net	18,238	9,801
Notes Receivable From Franchisees [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current accounts and notes receivable, gross	1,311	1,441
Noncurrent accounts and notes receivable, gross	8,562	6,810
Receivables From System Funds [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current accounts and notes receivable, gross	6,540	6,360
Noncurrent accounts and notes receivable, gross	10,113	3,033
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current accounts and notes receivable, gross	$ 9,775	$ 7,475