Investments - Summary of Sales of Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2022	Apr. 24, 2021	Apr. 25, 2020
Sales of marketable securities
Proceeds from sales	$ 35,116	$ 33,631	$ 36,443
Gross realized gains	879	1,026	852
Gross realized losses	(402)	$ (71)	$ (159)
Fair value of available-for-sale securities by contractual maturity
Within one year	16,018
Within two to five years	14,737
Within six to ten years	868
Thereafter	1,898
Total	$ 33,521

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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 rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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- Definition

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), excluding other-than-temporary impairment (OTTI).

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Amount of realized loss on 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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