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Financial Instruments and Fair Value - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jul. 31, 2024 | Jul. 31, 2023 | Jul. 31, 2024 | Jul. 31, 2023 | Jan. 31, 2024 | Jan. 31, 2023
Debt Securities, Available-for-Sale [Line Items] |  |  |  |  |  |
Interest income and realized gains and losses from financial instruments | $ 2,100,000 | $ 1,900,000 | $ 4,400,000 | $ 3,200,000 |  |
Carrying value of fixed deposit accounts | 153,925,000 | 122,515,000 | 153,925,000 | 122,515,000 | $ 144,914,000 | $ 113,541,000
Impairment losses on investment | 0 | $ 1,200,000 | 0 | $ 1,200,000 |  |
Non-marketable equity investment | 1,200,000 |  | 1,200,000 |  | 1,200,000 |
Fixed Deposit Accounts [Member] | Level 1 [Member] |  |  |  |  |  |
Debt Securities, Available-for-Sale [Line Items] |  |  |  |  |  |
Carrying value of fixed deposit accounts | $ 9,600,000 |  | $ 9,600,000 |  | $ 7,000,000 |

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