Marketable Securities - Summary of Company's Investments with Unrealized Losses, Aggregated by Investment Type (Detail) $ in Thousands	Apr. 30, 2022 USD ($)
Marketable Securities [Line Items]
Debt Securities, Less than 12 Months, Fair Value	$ 122,462
Debt Securities, Less than 12 Months, Unrealized Loss	(1,032)
Debt Securities, Greater than 12 Months, Fair Value	13,008
Debt Securities, Greater than 12 Months, Unrealized Loss	(99)
Debt Securities, Fair Value	135,470
Debt Securities, Unrealized Loss	(1,131)
Corporate Bond Securities [Member]
Marketable Securities [Line Items]
Debt Securities, Less than 12 Months, Fair Value	98,997
Debt Securities, Less than 12 Months, Unrealized Loss	(895)
Debt Securities, Greater than 12 Months, Fair Value	13,008
Debt Securities, Greater than 12 Months, Unrealized Loss	(99)
Debt Securities, Fair Value	112,005
Debt Securities, Unrealized Loss	(994)
Obligations of the U.S. Government and its Agencies [Member]
Marketable Securities [Line Items]
Debt Securities, Less than 12 Months, Fair Value	23,465
Debt Securities, Less than 12 Months, Unrealized Loss	(137)
Debt Securities, Fair Value	23,465
Debt Securities, Unrealized Loss	$ (137)

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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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 unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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