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Capital Stock - Additional Information (Detail) - USD ($) |  | 12 Months Ended
--- | --- | ---
Mar. 16, 2020 | Jan. 31, 2023 | Jan. 31, 2022 | Jan. 31, 2021
Class Of Stock [Line Items] |  |  |  |
Preference shares, shares authorized |  | 20,000,000 | 20,000,000 |
Preference shares, par value |  | $ 0.00045 | $ 0.00045 |
Preference shares, shares issued |  | 0 | 0 |
Preference shares, shares outstanding |  | 0 | 0 |
Stock repurchased, shares |  | 0 | 0 |
Stock repurchased during period, cash |  | $ 0 | $ 0 | $ 1,000,000
Stock Repurchase Program $50.0 Million Authorization [Member] |  |  |  |
Class Of Stock [Line Items] |  |  |  |
Stock repurchase program, expiration date |  | Jun. 30, 2023 |  |
Stock repurchased, shares | 25,719 |  |  |
Stock repurchased during period, cash | $ 1,000,000.0 |  |  |
Amount available under stock repurchase program |  | $ 49,000,000.0 |  |
Stock Repurchase Program $50.0 Million Authorization [Member] | Maximum [Member] |  |  |  |
Class Of Stock [Line Items] |  |  |  |
Amount authorized under stock repurchase program | $ 50,000,000.0 |  |  |

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