Refranchising Initiative Assets Held for Sale (Details) $ in Thousands	3 Months Ended
	Nov. 30, 2016 USD ($) franchise	Aug. 31, 2016 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Company Drive-Ins to be Sold | franchise	19
Property and equipment, net	$ 7,558	$ 5,299
Goodwill, net	90	0
Total assets held for sale	7,648	$ 5,299
Refranchising Initiative 2017 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Fair value adjustment on assets held for sale	$ 259