Investments - Available-for Sale Marketable Securities by Contractual Maturity (Details) - Debt Securities, Available-For-Sale, Excluding Money Market Accounts - USD ($) $ in Thousands	Apr. 30, 2022	Apr. 30, 2021
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
AFS Marketable Securities Maturities, Within one year, Amortized Cost	$ 622,517	$ 977,939
AFS Marketable Securities Maturities, After one year through five years, Amortized Cost	32,345	0
Amortized Cost	654,862	977,939
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
AFS Marketable Securities Maturities, Within one year, Fair Value	620,633	978,020
AFS Marketable Securities Maturities, After one year through five years, Fair Value	32,086	0
AFS Marketable Securities Maturities, Total Fair Value	$ 652,719	$ 978,020

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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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), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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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), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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