Fair Value Measurement (Details) - USD ($) $ in Thousands	Apr. 30, 2023	Jan. 31, 2023
Financial assets:
Total marketable securities	$ 474,781	$ 357,716
Commercial paper
Financial assets:
Total marketable securities	63,814	62,470
Treasury bills and U.S. government securities
Financial assets:
Total marketable securities	369,632	234,540
Corporate bonds
Financial assets:
Total marketable securities	24,933	46,486
Municipal bonds
Financial assets:
Total marketable securities	3,731	6,308
Agency bonds
Financial assets:
Total marketable securities	12,671	7,912
Recurring
Financial assets:
Total cash equivalents	698,071	329,769
Total marketable securities	474,781	357,716
Total	1,172,852	687,485
Recurring | Commercial paper
Financial assets:
Total marketable securities	63,814	62,470
Recurring | Treasury bills and U.S. government securities
Financial assets:
Total marketable securities	369,632	234,540
Recurring | Corporate bonds
Financial assets:
Total marketable securities	24,933	46,486
Recurring | Municipal bonds
Financial assets:
Total marketable securities	3,731	6,308
Recurring | Agency bonds
Financial assets:
Total marketable securities	12,671	7,912
Recurring | Money market
Financial assets:
Total cash equivalents	612,577	319,801
Recurring | Corporate bonds
Financial assets:
Total cash equivalents	24,137
Recurring | Commercial paper
Financial assets:
Total cash equivalents	55,690
Recurring | Agency bonds
Financial assets:
Total cash equivalents	5,667
Recurring | Treasury bills
Financial assets:
Total cash equivalents		9,968
Recurring | Level 1
Financial assets:
Total cash equivalents	618,244	329,769
Total marketable securities	382,303	242,452
Total	1,000,547	572,221
Recurring | Level 1 | Commercial paper
Financial assets:
Total marketable securities	0	0
Recurring | Level 1 | Treasury bills and U.S. government securities
Financial assets:
Total marketable securities	369,632	234,540
Recurring | Level 1 | Corporate bonds
Financial assets:
Total marketable securities	0	0
Recurring | Level 1 | Municipal bonds
Financial assets:
Total marketable securities	0	0
Recurring | Level 1 | Agency bonds
Financial assets:
Total marketable securities	12,671	7,912
Recurring | Level 1 | Money market
Financial assets:
Total cash equivalents	612,577	319,801
Recurring | Level 1 | Corporate bonds
Financial assets:
Total cash equivalents	0
Recurring | Level 1 | Commercial paper
Financial assets:
Total cash equivalents	0
Recurring | Level 1 | Agency bonds
Financial assets:
Total cash equivalents	5,667
Recurring | Level 1 | Treasury bills
Financial assets:
Total cash equivalents		9,968
Recurring | Level 2
Financial assets:
Total cash equivalents	79,827	0
Total marketable securities	92,478	115,264
Total	172,305	115,264
Recurring | Level 2 | Commercial paper
Financial assets:
Total marketable securities	63,814	62,470
Recurring | Level 2 | Treasury bills and U.S. government securities
Financial assets:
Total marketable securities	0	0
Recurring | Level 2 | Corporate bonds
Financial assets:
Total marketable securities	24,933	46,486
Recurring | Level 2 | Municipal bonds
Financial assets:
Total marketable securities	3,731	6,308
Recurring | Level 2 | Agency bonds
Financial assets:
Total marketable securities	0	0
Recurring | Level 2 | Money market
Financial assets:
Total cash equivalents	0	0
Recurring | Level 2 | Corporate bonds
Financial assets:
Total cash equivalents	24,137
Recurring | Level 2 | Commercial paper
Financial assets:
Total cash equivalents	55,690
Recurring | Level 2 | Agency bonds
Financial assets:
Total cash equivalents	0
Recurring | Level 2 | Treasury bills
Financial assets:
Total cash equivalents		0
Recurring | Level 3
Financial assets:
Total	$ 0	$ 0