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Equity - Additional Information (Detail) - USD ($) | 12 Months Ended |
--- | --- | ---
Aug. 31, 2025 | Aug. 31, 2024 | Aug. 31, 2023 | Jan. 08, 2025
Stockholders Equity Note [Line Items] |  |  |  |  |
Shares available for grant | 800,000 |  | 1,000,000 | 1,200,000 |
Performance based share based compensation and dividend equivalent rights | 312,000 | [1] | 400,000 | 500,000 |
Percentage of weighted EBITDA | 60.00% |  | 60.00% | 60.00% |
percentage of weighted ROIC | 20.00% |  | 20.00% | 20.00% |
Percentage of weighted peer group TSR | 20.00% |  | 20.00% | 20.00% |
Authorized amount under stock repurchase program | $ 100,000,000 |  |  |  |
Unamortized compensation cost of restricted stock unit grants | $ 18,000,000 |  |  |  |
Unamortized compensation cost of restricted stock unit grants expected to be recognized over weighted average period | 2 years |  |  |  |
Number of shares repurchased |  |  | 38,000 | 1,900,000 |
Share repurchase program, current authorization of shares purchased | 517,000 |  |  |  |
Number of shares repurchased amount |  |  | $ 1,300,000 | $ 56,900,000 |
Share repurchase program, current authorization of shares purchased amount | $ 22,200,000 |  |  |  |
Accrued excise taxes | 100,000 |  | 0 | 500,000 |
Remaining authorized repurchase amount | $ 77,800,000 |  |  |  | $ 100,000,000
Repurchase program expiration date | Jan. 31, 2027 |  |  |  |
Selling, Administrative and Cost of Revenue |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |
Restricted stock compensation expense | $ 17,500,000 |  | 17,100,000 | 12,100,000 |
Minimum |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |
Payout percentage | 0.00% |  |  |  |
Vesting period of compensation expense | 1 year |  |  |  |
Maximum |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |
Payout percentage | 200.00% |  |  |  |
Vesting period of compensation expense | 3 years |  |  |  |
Restricted Stock |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |
Restricted stock shares issued net of shares for tax withholdings | 400,000 |  |  |  |
Unvested Restricted Stock Grants |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |
Fair value of awards granted | $ 17,500,000 |  | $ 17,300,000 | $ 12,400,000 |
2021 Stock Incentive Plan |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |
Number of shares authorized | 2,200,000 |  |  |  |
2017 Amended and Restated Stock Incentive Plan |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |
Number of shares reserved | 700,000 |  |  |  |
[1] | Includes 143 thousand time-based and 169 thousand performance-based restricted stock unit awards.

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