Investments - Available-for-Sale Marketable Securities (Details) - USD ($) $ in Thousands	Oct. 31, 2021	Apr. 30, 2021	Oct. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	$ 167,436	$ 115,355	$ 114,603
Gross Unrealized Gains	29	101
Gross Unrealized Losses	(269)	(20)
Cash, cash equivalents and available-for-sale debt securities, amortized cost	1,005,925	1,021,340
Total cash equivalents and available-for-sale marketable securities	1,005,685	1,021,421
Money market funds
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	98,392	43,401
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	2,588	0
Amortized Cost	160,470	2,369
Gross Unrealized Gains	7	0
Gross Unrealized Losses	(245)	(1)
Estimated Fair Value	160,232	2,368
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,000	57,993
Gross Unrealized Gains	0	5
Gross Unrealized Losses	0	0
Estimated Fair Value	2,000	57,998
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	338,482	422,952
Gross Unrealized Gains	9	32
Gross Unrealized Losses	(1)	(6)
Estimated Fair Value	338,490	422,978
U.S. government agencies securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,815	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(22)	0
Estimated Fair Value	15,793	0
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	388,178	494,625
Gross Unrealized Gains	13	64
Gross Unrealized Losses	(1)	(13)
Estimated Fair Value	$ 388,190	$ 494,676

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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