Income Taxes Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 26, 2019	Oct. 27, 2018	Jan. 27, 2018	Jan. 26, 2019	Jan. 27, 2018
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit)	$ (294)		$ (15,344)	$ 2,680	$ (6,113)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	$ 475		$ (298,579)	$ 24,524	$ (275,736)
Effective Income Tax Rate Reconciliation, Percent	(61.90%)		5.10%	10.90%	2.20%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent				35.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent				21.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	$ 96	$ 3,815		$ 20,425
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	20.20%			15.90%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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