Income Taxes - Summary of Income Taxes Paid (Refunded) (Detail) - USD ($) $ in Thousands		12 Months Ended
		May 02, 2021	May 03, 2020	Apr. 28, 2019
Income Taxes [Line Items]
United States Federal - AMT credit refunds		$ 1,500
Total income tax payments, net		2,998	$ 4,995	$ 6,694
Domestic Tax Authority [Member] | United States [Member]
Income Taxes [Line Items]
United States Federal - AMT credit refunds	[1]	(1,510)
United States Federal - transition tax		226		600
U.S. State and Local Jurisdiction [Member] | United States [Member]
Income Taxes [Line Items]
Total income tax payments, net				60
Foreign Tax Authority [Member] | China [Member]
Income Taxes [Line Items]
Total income tax payments, net		2,874	3,397	3,543
Foreign Tax Authority [Member] | Canada [Member]
Income Taxes [Line Items]
Total income tax payments, net		$ 1,408	$ 1,598	$ 2,491

[1] In accordance with the TCJA, corporate taxpayers were eligible to treat prior AMT credit carryforwards as refundable. Accordingly, we elected to treat our prior AMT credit carryforward balance of $1.5 million as refundable, and as a result, 50% of the $1.5 million refundable balance was expected to be received in each of our fiscal years 2021 and 2022, respectively. We received our first 50% installment totaling $746,000 during the first quarter of fiscal 2021. In accordance with the CARES Act, 100% of AMT credit carryforwards for tax years beginning in the 2019 tax year were immediately refundable. Accordingly, we