Fair Value Measurements - Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jan. 31, 2024	Apr. 30, 2023
Available-for-sale marketable securities:
Total cash equivalents and available-for-sale marketable securities	$ 701,826	$ 717,717
Money market funds
Cash equivalents:
Estimated Fair Value	78,747	75,293
Certificates of deposit
Cash equivalents:
Estimated Fair Value	3,500	2,000
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	65,514	61,025
Commercial paper
Cash equivalents:
Estimated Fair Value	8,925	112,851
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	161,222	184,230
Corporate debt securities
Cash equivalents:
Estimated Fair Value	1,893	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	316,807	179,247
U.S. treasury securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	7,455	27,397
U.S. government agencies securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	57,763	75,674
Fair Value, Recurring
Available-for-sale marketable securities:
Total cash equivalents and available-for-sale marketable securities	701,826	717,717
Fair Value, Recurring | Money market funds
Cash equivalents:
Estimated Fair Value	78,747	75,293
Fair Value, Recurring | Certificates of deposit
Cash equivalents:
Estimated Fair Value	3,500	2,000
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	65,514	61,025
Fair Value, Recurring | Commercial paper
Cash equivalents:
Estimated Fair Value	8,925	112,851
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	161,222	184,230
Fair Value, Recurring | Corporate debt securities
Cash equivalents:
Estimated Fair Value	1,893	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	316,807	179,247
Fair Value, Recurring | U.S. treasury securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	7,455	27,397
Fair Value, Recurring | U.S. government agencies securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	57,763	75,674
Fair Value, Recurring | Level 1
Available-for-sale marketable securities:
Total cash equivalents and available-for-sale marketable securities	78,747	75,293
Fair Value, Recurring | Level 1 | Money market funds
Cash equivalents:
Estimated Fair Value	78,747	75,293
Fair Value, Recurring | Level 1 | Certificates of deposit
Cash equivalents:
Estimated Fair Value	0	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 1 | Commercial paper
Cash equivalents:
Estimated Fair Value	0	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 1 | Corporate debt securities
Cash equivalents:
Estimated Fair Value	0	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 1 | U.S. treasury securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 1 | U.S. government agencies securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 2
Available-for-sale marketable securities:
Total cash equivalents and available-for-sale marketable securities	623,079	642,424
Fair Value, Recurring | Level 2 | Money market funds
Cash equivalents:
Estimated Fair Value	0	0
Fair Value, Recurring | Level 2 | Certificates of deposit
Cash equivalents:
Estimated Fair Value	3,500	2,000
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	65,514	61,025
Fair Value, Recurring | Level 2 | Commercial paper
Cash equivalents:
Estimated Fair Value	8,925	112,851
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	161,222	184,230
Fair Value, Recurring | Level 2 | Corporate debt securities
Cash equivalents:
Estimated Fair Value	1,893	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	316,807	179,247
Fair Value, Recurring | Level 2 | U.S. treasury securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	7,455	27,397
Fair Value, Recurring | Level 2 | U.S. government agencies securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	57,763	75,674
Fair Value, Recurring | Level 3
Available-for-sale marketable securities:
Total cash equivalents and available-for-sale marketable securities	0	0
Fair Value, Recurring | Level 3 | Money market funds
Cash equivalents:
Estimated Fair Value	0	0
Fair Value, Recurring | Level 3 | Certificates of deposit
Cash equivalents:
Estimated Fair Value	0	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 3 | Commercial paper
Cash equivalents:
Estimated Fair Value	0	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 3 | Corporate debt securities
Cash equivalents:
Estimated Fair Value	0	0
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 3 | U.S. treasury securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	0	0
Fair Value, Recurring | Level 3 | U.S. government agencies securities
Available-for-sale marketable securities:
Available-for-sale marketable securities, fair value	$ 0	$ 0