Weighted-Average Assumptions (Detail) |
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] | |||
| Dividend yield | 0.15% | 0.19% | |
| Expected volatility | 38.12% | 38.06% | |
| Risk-free rate of return | 2.42% | 2.06% | |
| Expected forfeiture rate | 10.00% | 11.00% | 13.12% |
| Expected life | 7 years 5 months | 6 years 1 month | |
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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 The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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