Summary of Stock Option Activity (Detail) $ / shares in Units, $ in Millions |
12 Months Ended |
|---|---|
|
Aug. 31, 2020
USD ($)
$ / shares
shares
| |
| Number of Stock Option Outstanding | |
| Beginning Balance | shares | 1,606,543 |
| Granted | shares | 0 |
| Exercised | shares | (145,113) |
| Forfeited | shares | 0 |
| Expired | shares | (6,389) |
| Ending Balance | shares | 1,455,041 |
| Options exercisable at end of Period | shares | 1,323,188 |
| Weighted Average Exercise Price | |
| Beginning Balance | $ / shares | $ 25.88 |
| Granted | $ / shares | 0 |
| Exercised | $ / shares | 19.77 |
| Forfeited | $ / shares | 0 |
| Expired | $ / shares | 35.68 |
| Ending Balance | $ / shares | 26.45 |
| Options exercisable at end of Period | $ / shares | $ 26.55 |
| Option Outstanding weighted average remaining term | 3 years 6 months |
| Option exercisable weighted average remaining term | 3 years 3 months 18 days |
| Stock option, aggregate intrinsic Value | $ | $ 0.0 |
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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Options, Expired No definition available.
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Net number of share options (or share units) granted during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired. No definition available.
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- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. No definition available.
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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