Employee Benefits - Total Costs Associated with Plans (Details) - USD ($)	12 Months Ended
	Apr. 24, 2021	Apr. 25, 2020	Apr. 27, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net periodic pension cost	$ 0	$ 0	$ 35,998,000
401(k) Retirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Labor and related expense	7,313,000	9,380,000	9,128,000
Performance Compensation Retirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Labor and related expense	3,810,000	1,115,000	3,084,000
Deferred Compensation Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Labor and related expense	24,000	719,000	284,000
Non-Qualified Defined Benefit Retirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Labor and related expense	$ 803,000	$ 796,000	$ 805,000