Investments - Sales and Maturities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 28, 2023	Jan. 22, 2022	Jan. 28, 2023	Jan. 22, 2022
Sales of Marketable Securities
Proceeds from sales	$ 5,514	$ 7,784	$ 18,178	$ 29,437
Gross realized gains	3	142	52	696
Gross realized losses	(81)	$ (20)	(207)	$ (356)
Fair Value of Available-For-Sale Securities By Contractual Maturity
Within one year	10,907		10,907
Within two to five years	7,836		7,836
Within six to ten years	572		572
Thereafter	1,886		1,886
Total	$ 21,201		$ 21,201

No definition available.

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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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No definition available.

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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 after rolling tenth 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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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 rolling sixth through tenth 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
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27198-111563

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Amount of cash inflow from sale 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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