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- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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- Definition

Amount of the item included in the interim period that affected period-to-period comparability (excluding restatement adjustments).

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Selected Quarterly Financial Data (Unaudited) (Schedule Of Selected Quarterly Financial Data) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Aug. 31, 2018	May 31, 2018	Feb. 28, 2018	Nov. 30, 2017	Aug. 31, 2017	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016
Selected Quarterly Financial Data [Line Items]
Total revenues	$ 111,754	$ 118,306	$ 88,102	$ 105,428	$ 123,568	$ 123,990	$ 100,158	$ 129,551	$ 423,590	$ 477,267	$ 606,320
Income from operations	31,780	37,261	14,914	22,448	38,155	35,441	22,627	27,052	106,403	123,275	127,452
Net income	$ 18,592	$ 21,576	$ 19,607	$ 11,430	$ 20,831	$ 18,751	$ 10,963	$ 13,118	$ 71,205	$ 63,663	$ 64,067
Basic income per share (usd per share)	$ 0.52	$ 0.58	$ 0.51	$ 0.29	$ 0.50	$ 0.44	$ 0.25	$ 0.29	$ 1.89	$ 1.47	$ 1.32
Diluted income per share (usd per share)	$ 0.51	$ 0.58	$ 0.51	$ 0.29	$ 0.50	$ 0.44	$ 0.25	$ 0.28	$ 1.87	$ 1.45	$ 1.29
After tax expense related to cybersecurity incident [Member]
Selected Quarterly Financial Data [Line Items]
Quarterly charges (credits) that affect comparability	$ 300	$ 200	$ 200	$ 400
After tax loss from debt transactions [Member]
Selected Quarterly Financial Data [Line Items]
Quarterly charges (credits) that affect comparability			900
Impact of Tax Cuts and Jobs Act [Member]
Selected Quarterly Financial Data [Line Items]
Quarterly charges (credits) that affect comparability			$ (14,100)
After tax (gain) loss on refranchising transactions [Member]
Selected Quarterly Financial Data [Line Items]
Quarterly charges (credits) that affect comparability		$ (2,200)			$ (100)	$ (400)	$ (4,300)	$ 600
After tax gain on sale of investment in refranchised drive-in operations [Member]
Selected Quarterly Financial Data [Line Items]
Quarterly charges (credits) that affect comparability								$ (2,400)
After tax restructuring charges [Member]
Selected Quarterly Financial Data [Line Items]
Quarterly charges (credits) that affect comparability					1,100
After tax gain on sale of real estate [Member]
Selected Quarterly Financial Data [Line Items]
Quarterly charges (credits) that affect comparability					$ (3,000)