Credit Losses - Schedule of Fair Value and Unrealized Losses on Available for Sale Debt Securities (Detail) - USD ($) $ in Thousands	Apr. 30, 2025	Apr. 30, 2024
Commercial paper
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Less than 12 months, fair value	$ 3,841	$ 11,040
Less than 12 months, unrealized losses	1	19
12 months or longer, fair value	0	0
12 months or longer, unrealized losses	0	0
Commercial paper \| Cash and Cash Equivalents
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Debt securities AFS, fair value	500	3,932
Commercial paper \| Marketable Securities, Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Debt securities, current	3,341	7,108
Commercial paper \| Marketable Securities, Non-Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Debt 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	7,803	11,022
Less than 12 months, unrealized losses	10	26
12 months or longer, fair value	0	1,999
12 months or longer, unrealized losses	0	1
Corporate notes/bonds \| Cash and Cash Equivalents
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Debt securities AFS, fair value	0	0
Corporate notes/bonds \| Marketable Securities, Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Debt securities, current	4,630	9,050
Corporate notes/bonds \| Marketable Securities, Non-Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Debt securities, non-current	$ 3,173	3,971
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		4,346
Less than 12 months, unrealized losses		9
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]
Debt securities AFS, fair value		0
U.S. Treasury and Agency Securities \| Marketable Securities, Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Debt securities, current		2,441
U.S. Treasury and Agency Securities \| Marketable Securities, Non-Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Debt securities, non-current		$ 1,905

Fair value and unrealized losses on available for sale debt securities.

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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 accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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