Investments - Sales and Maturities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 27, 2024	Jan. 28, 2023	Jan. 27, 2024	Jan. 28, 2023
Sales of Marketable Securities
Proceeds from sales	$ 1,381	$ 5,514	$ 21,849	$ 18,178
Gross realized gains	33	3	1,909	52
Gross realized losses	0	$ (81)	(740)	$ (207)
Fair Value of Available-For-Sale Securities By Contractual Maturity
Within one year	6,445		6,445
Securities not due at a single maturity date	6,600		6,600
Total	$ 13,045		$ 13,045

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