v3.25.1
Fair Value Measurements - Marketable Securities (Details) - U.S. government treasury securities - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Apr. 30, 2025
Jan. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Amortized cost, due withen one year $ 1,028,664 $ 968,748
Amortized cost, due after one year and withen three years 759,066 876,154
Amortized cost, total 1,787,730 1,844,902
Unrealized loss, due withen one year 1,602 944
Due after one year and within three years 6,797 598
Total short-term investments 8,399 1,542
Short-term investments 1,030,266 969,692
Marketable securities, non-current 765,863 876,752
Total short-term investments $ 1,796,129 $ 1,846,444