Credit Losses - Schedule of Fair Value and Unrealized Losses on Available for Sale Debt Securities (Detail) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Commercial Paper
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Less Than 12 Months, Fair Value	$ 32,373	$ 36,378
Less Than 12 Months, Unrealized Loss	34	7
Commercial Paper \| Cash and Cash Equivalents
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Fair Value	1,999	5,749
Commercial Paper \| Marketable Securities Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Available For Sale Securities Debt Securities, Current	30,374	30,629
Corporate Notes/Bonds
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Less Than 12 Months, Fair Value	39,780	26,350
Less Than 12 Months, Unrealized Loss	171	20
Corporate Notes/Bonds \| Marketable Securities Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Available For Sale Securities Debt Securities, Current	24,381	10,133
Corporate Notes/Bonds \| Marketable Securities Non-Current
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]
Available For Sale Securities Debt Securities, Non-Current	$ 15,399	$ 16,217

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 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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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