Customer Financing (Detail)	3 Months Ended		9 Months Ended
	Jan. 28, 2023 USD ($)	Jan. 29, 2022 USD ($)	Jan. 28, 2023 USD ($) financingAgreement	Jan. 29, 2022 USD ($)	Apr. 30, 2022 USD ($)
Customer Financing [Line Items]
Maximum credit financed for equipment purchases for any one customer	$ 1,000,000		$ 1,000,000
Number of customer financing contracts | financingAgreement			2
Financing contracts sold			$ 205,140,000	$ 225,300,000
Gain (loss) on sale of financing contracts	(3,254,000)	$ (663,000)	(7,900,000)	(2,278,000)
Proceeds from Receivables sold			238,091,000	327,205,000
Cash and cash equivalents	147,290,000		147,290,000		$ 142,014,000
Current receivables of finance contracts not yet sold	36,454,000		36,454,000		58,190,000
Finance contracts receivable sold and outstanding	562,325,000		$ 562,325,000
Bad debt write-offs, percentage (less than)			1.00%
Unsettled Financing Arrangements
Customer Financing [Line Items]
Cash and cash equivalents	30,846,000		$ 30,846,000		$ 39,106,000
Customer Finance Contracts
Customer Financing [Line Items]
Gain (loss) on sale of financing contracts	2,417,000	$ (5,143,000)	$ (5,051,000)	$ (8,433,000)
The Bank of Tokyo-Mitsubishi UFJ, Ltd.
Customer Financing [Line Items]
Percentage of principal amount of financing contracts held as collateral (at least)			15.00%
Capacity under agreement	525,000,000		$ 525,000,000
Fifth Third Bank
Customer Financing [Line Items]
Percentage of principal amount of financing contracts held as collateral (at least)			15.00%
Capacity under agreement	$ 100,000,000		$ 100,000,000