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Financial Instruments and Fair Value - Schedule of Available-for-Sale Securities at Fair Value (Detail) - USD ($) $ in Thousands | Apr. 30, 2025 | Jan. 31, 2025
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 117,965 | $ 109,725
Unrealized Gains | 444 | 139
Unrealized Losses | (118) | (372)
Fair Value | 118,291 | 109,492
Money market funds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 189 | 849
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Fair Value | 189 | 849
Fixed deposits [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 0 | 3,000
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Fair Value | 0 | 3,000
Corporate bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 62,210 | 55,138
Unrealized Gains | 267 | 111
Unrealized Losses | (34) | (123)
Fair Value | 62,443 | 55,126
Asset-backed securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 21,288 | 20,412
Unrealized Gains | 50 | 20
Unrealized Losses | (50) | (67)
Fair Value | 21,288 | 20,365
U.S. government securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 34,278 | 30,326
Unrealized Gains | 127 | 8
Unrealized Losses | (34) | (182)
Fair Value | $ 34,371 | $ 30,152

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