Share-Based Compensation (Summary of Share Based Compensation Additional Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Intrinsic value of stock options exercised	$ 93	$ 538	$ 681
Cash received from stock option exercises	177	2,788	3,020
Tax benefit realized from stock option exercises	$ 26	$ 151	$ 254
Weighted average grant-date fair value of stock options vested	$ 32.66	$ 31.37	$ 35.79

Share based compensation arrangement by share based payment award equity instruments stock options grants in period weighted average grant date fair value.

No definition available.

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- Definition

Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise.

+ References

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=SL79508275-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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