Selected Financial Statement Data - Other (Expense) Income (Details) - USD ($) $ in Thousands	12 Months Ended
May 02, 2020	Apr. 27, 2019	Apr. 28, 2018
Selected Financial Statement Data [Abstract]
Foreign currency transaction gains (losses)	$ 207	$ (262)	$ 29
Equity in losses of affiliates	(741)	(844)	(481)
Other Nonoperating Expense	(7)		(85)
Other Nonoperating Income		19
Other (expense) income, net	$ (541)	$ (1,087)	$ (537)

Selected Financial Statement Data [Abstract]

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount of income related to nonoperating activities, classified as other.

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