Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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Shareholders' Equity - Allocated Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Apr. 27, 2019	Apr. 28, 2018	Apr. 29, 2017
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense	$ 14.0	$ 4.0	$ 12.4
Unrecognized equity-based compensation cost	6.6
2014 Incentive Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense	14.0	4.0	12.1
Unrecognized equity-based compensation cost	6.6
2014 Incentive Plan \| RSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense	2.2	5.0	5.5
Unearned compensation expense	1.6
2010 Stock Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense			0.2
2010 Stock Plan \| RSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense	0.0	0.0	0.1
Unearned compensation expense	0.0
2010 Stock Plan \| Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense	0.0	0.0	0.1
Unearned compensation expense	0.0
2007 Stock Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense			0.1
2007 Stock Plan \| Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense	0.0	0.0	0.1
Unearned compensation expense	0.0
Executives and non-executive members of management \| 2014 Incentive Plan \| RSAs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense	10.9	(2.0)	5.7
Unearned compensation expense	5.0
Independent directors \| 2014 Incentive Plan \| RSAs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expense	0.9	$ 1.0	$ 0.9
Unearned compensation expense	$ 0.0