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Interim Financial Statements - Additional Information (Detail) - USD ($) $ in Millions |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jan. 05, 2023 | May 31, 2023 | May 31, 2023 | May 31, 2022
Equity Class Of Treasury Stock [Line Items] |  |  |  |
Stock repurchased authorized amount |  | $ 100.0 | $ 100.0 |
Stock repurchase program remaining authorized repurchase amount |  | $ 53.9 | $ 53.9 |
Stock repurchase program number of shares repurchased |  |  |  | 0
Number of shares repurchased |  | 1,200,000 | 1,700,000 |
Number of shares repurchased amount |  | $ 32.0 | $ 49.4 |
Share repurchase program, current authorization of shares purchased |  |  | 1,600,000 |
Share repurchase program, current authorization of shares purchased amount |  |  | $ 46.1 |
Share repurchase program expiration date |  |  | Jan. 31, 2023 |
Stock repurchase program extension date | Jan. 31, 2025 |  |  |

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