Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Oct. 27, 2018	Oct. 28, 2017	Oct. 27, 2018	Oct. 28, 2017	Apr. 28, 2018
Income Tax Disclosure [Abstract]
Effective income tax rate	24.00%	34.50%	25.10%	34.50%
Blended income tax rate, percent					30.50%
Tax Cuts And Jobs Act Of 2017,incomplete accounting, provisional income tax benefit					$ (76,648)
Tax Cuts And Jobs Act Of 2017, incomplete accounting, change in tax rate, deferred taxes, provisional income tax expense					81,871
Tax Cuts And Jobs Act Of 2017, incomplete accounting, transition tax for unremitted foreign earnings					(4,006)
Tax Cuts And Jobs Act of 2017, incomplete Accounting, transition tax withholding associated with repatriation of foreign earnings					$ 1,217