Stockholders' Equity (Option Activity) (Details 4) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Aug. 31, 2017	Aug. 31, 2016
Stockholders' Equity [Abstract]
SARS Outstanding, SARS canceled	(1,357,386)
SARS Outstanding, SARS exercised	(762,439)
SARS Outstanding, exercisable ending balance	319,241	2,439,066
Aggregate Intrinsic Value, Exercisable ending balance	$ 3,651	$ 1,066
Weighted-Average Exercise Price, SARS canceled	$ 29.15
Weighted-Average Exercise Price, SARS exercised	20.78
Weighted-Average Exercise Price, exercisable ending balance	$ 19.91	$ 25.32
Weighted-Average Remaining Contractual Life	2 years 2 months 156 days	1 year 1 month 17 days
Weighted-Average Remaining Contractual Life, Exercisable ending balance	2 years 2 months 156 days

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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

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