Investments - Available-for-Sale Marketable Securities (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021	Jan. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	$ 204,531	$ 115,355	$ 960,122
Gross Unrealized Gains	7	101
Gross Unrealized Losses	(803)	(20)
Cash, cash equivalents and available-for-sale debt securities, amortized cost	961,169	1,021,340
Total cash equivalents and available-for-sale marketable securities	960,373	1,021,421
Money market funds
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	129,753	43,401
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	10,998	0
Amortized Cost	308,205	494,625
Gross Unrealized Gains	3	64
Gross Unrealized Losses	0	(13)
Estimated Fair Value	308,208	494,676
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	1,506	0
Amortized Cost	196,210	2,369
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(698)	(1)
Estimated Fair Value	195,512	2,368
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	57,993
Gross Unrealized Gains	0	5
Gross Unrealized Losses	0	0
Estimated Fair Value	0	57,998
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	300,377	422,952
Gross Unrealized Gains	4	32
Gross Unrealized Losses	0	(6)
Estimated Fair Value	300,381	422,978
U.S. government agencies securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	14,120	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(105)	0
Estimated Fair Value	$ 14,015	$ 0

Cash, Cash Equivalents And Available-for-sale Debt Securities

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Cash, Cash Equivalents And Available-for-sale Debt Securities, Amortized Cost

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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