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Earnings Per Share - Additional Information (Detail) |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 29, 2025 USD ($) Director shares | Jun. 05, 2025 USD ($) Director shares | Mar. 01, 2025 USD ($) shares | Dec. 05, 2024 USD ($) Director shares | Jun. 06, 2024 USD ($) Director shares | Mar. 01, 2024 USD ($) shares | Aug. 31, 2025 USD ($) shares | Sep. 30, 2024 USD ($) shares
Earnings Per Share [Line Items] |  |  |  |  |  |  |  |
Number of directors received shares | shares | 288 | 762 |  | 54 | 716 |  |  |
Number of directors received shares | Director | 1 | 10 |  | 1 | 12 |  |  |
Compensation annual basis committee award | $ | $ 7,436 | $ 17,496 |  | $ 1,730 | $ 15,007 |  |  |
Senior Management |  |  |  |  |  |  |  |
Earnings Per Share [Line Items] |  |  |  |  |  |  |  |
Restricted stock awards, Shares | shares |  |  | 19,767 |  |  | 23,369 |  |
Restricted stock awards | $ |  |  | $ 508,012 |  |  | $ 472,054 |  |
Other Members of Management |  |  |  |  |  |  |  |
Earnings Per Share [Line Items] |  |  |  |  |  |  |  |
Restricted stock awards, Shares | shares |  |  |  |  |  |  | 39,525 | 36,800
Restricted stock awards | $ |  |  |  |  |  |  | $ 1,000,000 | $ 979,616
One Director |  |  |  |  |  |  |  |
Earnings Per Share [Line Items] |  |  |  |  |  |  |  |
Number of directors received shares | shares |  | 292 |  |  | 282 |  |  |
Number of directors received shares | Director |  | 1 |  |  | 1 |  |  |
Compensation annual basis committee award | $ |  | $ 6,704 |  |  | $ 5,911 |  |  |

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