Stockholders' Equity (SARs Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017
SARS Outstanding
SARS canceled (in shares)	(35,439)
SARs
SARS Outstanding
SARS Outstanding as of beginning of period (in shares)	319,241
SARS canceled (in shares)	(35,439)
SARS exercised (in shares)	(127,001)
SARS Outstanding as of end of period (in shares)	156,801	319,241
SARS, Exercisable (in shares)	319,241
Aggregate Intrinsic Value, Outstanding	$ 1,748	$ 3,651
Aggregate Intrinsic Value, Exercisable	$ 3,651
Weighted- Average Exercise Price
Weighted-Average Exercise Price, Outstanding as of beginning of period (in dollars per share)	$ 19.91
Weighted-Average Exercise Price, SARS canceled (in dollars per share)	21.56
Weighted-Average Exercise Price, SARS exercised (in dollars per share)	21.31
Weighted-Average Exercise Price, Outstanding as of end of period (in dollars per share)	18.41	$ 19.91
Weighted-Average Exercise Price, Exercisable (in dollars per share)	$ 18.41
Weighted- Average Remaining Contractual Life, Outstanding	3 years 1 month 6 days	2 years 1 month 6 days
Weighted- Average Remaining Contractual Life, Exercisable	2 years 1 month 6 days

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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Number of share options (or share units) exercised during the current period.

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