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Equity - Additional Information (Detail) - USD ($) | 12 Months Ended |
--- | --- | ---
Aug. 31, 2022 | Aug. 31, 2021 | Aug. 31, 2020 | Jan. 06, 2021
Stockholders Equity Note [Line Items] |  |  |  |
Shares repurchased |  | $ 20,000,000.0 |  |
Shares available for grant | 1,394,000 | 1,618,000 | 466,000 |
Performance based share based compensation and dividend equivalent rights | 391,000 | 538,000 | 470,000 |
Share based compensation, non vested shares | 653,000 |  |  |
Additional shares available for grant | 653,000 |  |  |
Unamortized compensation cost of restricted stock unit grants | $ 12,800,000 |  |  |
Share Repurchase Program - 2014 |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |
Remaining authorized repurchase amount | $ 100,000,000.0 |  |  |
Repurchase program expiration date | Jan. 31, 2023 |  |  |
Repurchase of common stock, shares | 0 | 0 | 0 |
Selling, Administrative and Cost of Revenue |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |
Restricted stock compensation expense | $ 15,500,000 | $ 14,700,000 | $ 8,700,000 |
Restricted Stock |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |
Restricted stock shares issued net of shares for tax withholdings | 290,000 |  |  |
Restricted Stock | Minimum |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |
Vesting period of compensation expense | 1 year |  |  |
Restricted Stock | Maximum |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |
Vesting period of compensation expense | 3 years |  |  |
Unvested Restricted Stock Grants |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |
Share based compensation, non vested shares | 1,042,000 | 1,024,000 |  |
Fair value of awards granted | $ 18,700,000 | $ 18,000,000.0 | $ 14,500,000 |
2021 Stock Incentive Plan and 2017 Amended and Restated Stock Incentive Plan |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |
Number of shares reserved for future issuance |  |  |  | 1,500,000
2021 Stock Incentive Plan and 2017 Amended and Restated Stock Incentive Plan | Maximum |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |
Shares available for grant |  |  |  | 466,000
Number of common shares outstanding |  |  |  | 884,000

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