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Financial Instruments and Fair Value - Schedule of Fair Value of Financial Instruments Measured on Recurring Basis (Detail) - USD ($) $ in Thousands | Jul. 31, 2025 | Jan. 31, 2025
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | $ 126,306 | $ 109,492
Money market funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 861 | 849
Fixed deposits [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 7,001 | 3,000
Corporate bonds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 61,728 | 55,126
Asset-backed securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 20,362 | 20,365
U.S. government securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 36,354 | 30,152
Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 7,862 | 3,849
Level 1 [Member] | Money market funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 861 | 849
Level 1 [Member] | Fixed deposits [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 7,001 | 3,000
Level 1 [Member] | Corporate bonds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 1 [Member] | Asset-backed securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 1 [Member] | U.S. government securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 118,444 | 105,643
Level 2 [Member] | Money market funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 2 [Member] | Fixed deposits [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 2 [Member] | Corporate bonds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 61,728 | 55,126
Level 2 [Member] | Asset-backed securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 20,362 | 20,365
Level 2 [Member] | U.S. government securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 36,354 | 30,152
Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 3 [Member] | Money market funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 3 [Member] | Fixed deposits [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 3 [Member] | Corporate bonds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 3 [Member] | Asset-backed securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | 0 | 0
Level 3 [Member] | U.S. government securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total cash equivalents and marketable debt securities | $ 0 | $ 0

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