Financial Instruments and Fair Value - Summary of Contractual Maturities of Investments (Detail) - USD ($) $ in Thousands |
Jan. 31, 2022 |
Jan. 31, 2021 |
|---|---|---|
| Available For Sale Securities Debt Maturities Fair Value [Abstract] | ||
| Due within one year | $ 20 | $ 135,899 |
| Due within one to three years | 0 | 78,903 |
| Total cash equivalents and marketable debt securities | $ 20 | $ 214,802 |