Shareholders' Equity - Stock-based Compensation Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	May 01, 2021	May 02, 2020	Apr. 27, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 0.0
2014 Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	6.8	$ 0.3	$ 14.0
2014 Incentive Plan | RSAs | Management
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	0.0	(2.1)	10.9
2014 Incentive Plan | RSAs | Director
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	0.9	0.9	0.9
2014 Incentive Plan | RSUs | Management
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 5.9	$ 1.5	$ 2.2