Schedule II Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 24, 2021	Apr. 25, 2020	Apr. 27, 2019
Allowance for doubtful accounts [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 5,123	$ 6,772	$ 9,537
Charged to Costs and Expenses	2,559	2,008	7,333
Charged to Other Accounts	0	0	0
Deductions	1,544	3,657	10,098
Balance at End of Period	6,138	5,123	6,772
LIFO inventory adjustment [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	99,726	91,342	82,105
Charged to Costs and Expenses	21,049	8,384	9,237
Charged to Other Accounts	0	0	0
Deductions	0	0	0
Balance at End of Period	120,775	99,726	91,342
Inventory obsolescence reserve [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	25,526	10,099	5,376
Charged to Costs and Expenses	45,761	27,405	30,995
Charged to Other Accounts	0	0	0
Deductions	41,658	11,978	26,272
Balance at End of Period	29,629	25,526	10,099
Total inventory reserve [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	125,252	101,441	87,481
Charged to Costs and Expenses	66,810	35,789	40,232
Charged to Other Accounts	0	0	0
Deductions	41,658	11,978	26,272
Balance at End of Period	$ 150,404	$ 125,252	$ 101,441