Supplementary Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Oct. 31, 2020	Oct. 26, 2019	Oct. 31, 2020	Oct. 26, 2019
Other Nonrecurring Expense	$ 0	$ 0	$ 0	$ 433
Restructuring and other charges	3,387	1,569	9,058	3,035
Employee Severance [Member]
Restructuring and other charges	1,075	88	4,471	819
Other Restructuring [Member]
Restructuring and other charges	2,255	$ 1,481	4,472	$ 2,216
Facility Closing [Member]
Restructuring and other charges	57		114
Employee Severance [Member]
Accrued Salaries	$ 7,092		$ 7,092

Carrying value as of the balance sheet date of the obligations incurred through that date and payable for employees' services provided.

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