Summary of Weighted-Average Grant-Date Fair Value of Options, Total Intrinsic Value of Options Exercised, and Cash Receipts from Options Exercised (Detail) - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | ||
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Aug. 31, 2018 |
Aug. 31, 2017 |
Aug. 31, 2016 |
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| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |||
| Weighted-average fair value of options granted (per share) | $ 11.88 | $ 8.63 | |
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value | $ 5,284 | $ 2,208 | $ 989 |
| Cash receipts from exercise of options | $ 15,140 | $ 7,762 | $ 3,564 |
| Expected forfeiture rate | 10.00% | 11.00% | 13.12% |
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- Definition Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Forfeiture Rate No definition available.
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- References No definition available.
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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