Refranchising Initiative Summary of the pretax activity recorded as a result of the refranchising initiative (Details) $ in Thousands	3 Months Ended
Nov. 30, 2017 USD ($)	Nov. 30, 2016 USD ($) franchise
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sales of Company Drive-Ins	$ 685	$ 10,826
Refranchising Initiative 2017 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of refranchised Company Drive-Ins \| franchise		56
Proceeds from sales of Company Drive-Ins		$ 8,950
Initial lease payments for real estate option		(3,810)
Goodwill related to sales of Company Drive-Ins		(377)
Loss on assets held for sale		(259)
Refranchising initiative losses, net		$ (957)
Refranchised Company Drive-Ins with Direct Financing Lease \| franchise		53
Equipment [Member] \| Refranchising Initiative 2017 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets sold, net of retained minority investment		$ (5,461)

Number of Company Drive-Ins refranchised during the period

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Refranchised Company Drive-Ins with Direct Financing Lease

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2443-110228

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash inflow associated with the collection of receivables arising from the lease of real estate, equipment or other fixed assets for a specified time in exchange for payment, usually in the form of rent; excludes proceeds from sales-type lease transactions, which are classified as operating activities.

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Amount of divestiture of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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