Cash Equivalents and Marketable Securities - Available-for Sale Debt Securities by Contractual Maturity (Details) - Debt Securities, Available-For-Sale, Excluding Money Market Accounts - USD ($) $ in Thousands	Jan. 31, 2025	Apr. 30, 2024
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
AFS debt maturities, within one year, amortized cost	$ 494,233	$ 514,747
AFS debt maturities, after one year through five years, amortized cost	104,706	69,034
Amortized Cost	598,939	583,781
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
AFS debt maturities, within one year, fair value	494,937	514,484
AFS debt maturities, after one year through five years, fair value	104,296	68,736
AFS debt maturities, total fair value	$ 599,233	$ 583,220