Derivative Financial Instruments - Fair Value of Derivative Instruments Included in Condensed Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Jan. 23, 2021	Apr. 25, 2020
Derivatives, Fair Value [Line Items]
Interest rate contracts, assets, fair value	$ 578	$ 204
Interest rate contracts, liabilities, fair value	13,987	19,849
Other Noncurrent Assets | Interest rate contracts
Derivatives, Fair Value [Line Items]
Interest rate contracts, assets, fair value	578	204
Other Accrued Liabilities | Interest rate contracts
Derivatives, Fair Value [Line Items]
Interest rate contracts, liabilities, fair value	4,695	6,789
Other Noncurrent Liabilities | Interest rate contracts
Derivatives, Fair Value [Line Items]
Interest rate contracts, liabilities, fair value	$ 9,292	$ 13,060