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Capital Stock - Additional Information (Detail) - USD ($) $ in Millions |  | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Oct. 31, 2024 | Jan. 31, 2024
Class Of Stock [Line Items] |  |  |
Preference shares, shares issued |  | 0 | 0
Preference shares, shares outstanding |  | 0 | 0
Share Repurchase Program [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Stock repurchased, shares |  | 0 |
Amount available under stock repurchase program |  | $ 49.0 |
Share Repurchase Program [Member] | Forecast [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Stock repurchase program, expiration date | Jun. 30, 2025 |  |
ESPP [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Additional ordinary shares reserved for issuance |  | 994,543 |
ESPP [Member] | Scenario, plan automatically increased by the lessor of [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Annual increase in ordinary shares for available for future issuance |  | 1,500,000 |
Annual shares increase for future issuance by percentage under 2012 employee stock purchase plan |  | 1.25% |
2021 EIP [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Additional ordinary shares reserved for issuance |  | 1,750,000 |
Ordinary shares reserved for issuance |  | 3,100,000 |
Maximum number of ordinary shares reserved for issuance |  | 6,834,208 |

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