Summary of Significant Accounting Policies - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Apr. 25, 2020	Apr. 28, 2019	Apr. 27, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets, net	$ 79,021		$ 0
Operating lease liabilities	$ 80,560
ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets, net		$ 86,046
Operating lease liabilities		88,333
Deferred gain on sales leaseback transactions		$ 1,447