Credit Losses - Schedule of Fair Value and Unrealized Losses on Available for Sale Debt Securities (Detail) - USD ($) $ in Thousands	Apr. 30, 2023	Apr. 30, 2022
Commercial paper
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Less Than 12 Months, Fair Value	$ 8,229	$ 37,002
Less Than 12 Months, Unrealized Losses	26	125
12 Months or longer, Fair Value	3,492	4,499
12 Months or longer, Unrealized Losses	4	1
Commercial paper \| Cash and Cash Equivalents
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Cash and Cash Equivalents	0	15,489
Commercial paper \| Marketable Securities, Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Marketable Securities, Current	11,721	26,012
Commercial paper \| Marketable Securities, Non- Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Marketable Securities, Non- Current	0	0
Corporate notes/bonds
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Less Than 12 Months, Fair Value	9,581	32,186
Less Than 12 Months, Unrealized Losses	123	446
12 Months or longer, Fair Value	13,815	3,800
12 Months or longer, Unrealized Losses	232	4
Corporate notes/bonds \| Cash and Cash Equivalents
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Cash and Cash Equivalents	0	0
Corporate notes/bonds \| Marketable Securities, Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Marketable Securities, Current	20,489	18,942
Corporate notes/bonds \| Marketable Securities, Non- Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Marketable Securities, Non- Current	$ 2,907	17,044
U.S. Treasury and Agency Securities
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Less Than 12 Months, Fair Value		987
Less Than 12 Months, Unrealized Losses		8
12 Months or longer, Fair Value		0
12 Months or longer, Unrealized Losses		0
U.S. Treasury and Agency Securities \| Cash and Cash Equivalents
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Cash and Cash Equivalents		0
U.S. Treasury and Agency Securities \| Marketable Securities, Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Marketable Securities, Current		987
U.S. Treasury and Agency Securities \| Marketable Securities, Non- Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Marketable Securities, Non- Current		$ 0

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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 investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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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), classified as noncurrent.

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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