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Debt (Details) - USD ($) $ in Thousands	12 Months Ended
Debt (Details) - USD ($) $ in Thousands	Apr. 27, 2019	Apr. 28, 2018	Apr. 29, 2017
Debt
Less: current portion	$ (180)	$ (223)
Long-term debt	19	199
Cash paid for interest	1,000	400	$ 500
Capital leases
Debt
Total debt	199	422
Less: current portion	(180)	(223)
Long-term debt	19	199
Maturities of long-term capital leases
Fiscal 2020	$ 200
Capital leases \| Minimum
Debt
Interest rate (as a percent)	2.60%
Capital leases \| Maximum
Debt
Interest rate (as a percent)	2.70%
Revolving credit facility
Debt
Borrowings outstanding	$ 0	$ 0
Excess availability	148,100
Credit commitment	$ 150,000