Allocated Share-based Compensation Expense, Amount Recorded to True-up Prior Periods

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- Definition

Deferred RSU's

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- Definition

Percentage achieved of annual average EBITDA at target.

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- Definition

Share-based compensation arrangement by share-based payment award, equity instruments other than options, vested but deferred for issuance.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, EBITDA Goal, Percentage of Likelihood

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Remaining for Award

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No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Description of terms of share-based payment arrangement. Includes, but is not limited to, type of award or grantee and reason for issuance.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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Number of shares issued under share-based payment arrangement.

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- Definition

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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Shareholders' Equity - Narrative (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	May 02, 2020	Feb. 01, 2020	Oct. 26, 2019	Jul. 27, 2019	Apr. 27, 2019	Jan. 26, 2019	Oct. 27, 2018	Jul. 28, 2018	May 02, 2020	Apr. 27, 2019	Apr. 28, 2018	Apr. 30, 2007
2014 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	3,000,000								3,000,000
Stock-based compensation, description									The number of shares of common stock originally authorized under the 2014 Plan is 3,000,000, less one share for every one share of common stock issued or issuable pursuant to awards made after May 3, 2014 under the 2007 Plan or 2010 Plan.
Number of shares available for award (in shares)	1,897,442								1,897,442
Compensation expense									$ 0.3	$ 14.0	$ 4.0
Deferred RSU's	121,200								121,200
2014 Incentive Plan \| RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EBITDA goal, percentage of likelihood									70.00%
Number of restricted stock, vested									444,500
2014 Incentive Plan \| RSAs \| Independent directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense									$ 0.9	$ 0.9	$ 1.0
Number of shares issued (in shares)									30,000	24,000	24,000
2014 Incentive Plan \| RSAs \| Executives and non-executive members of management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense, amount recorded to true-up prior periods	$ (6.5)	$ 0.0	$ 0.0	$ 0.0	$ 0.0	$ 0.0	$ 7.4	$ 0.0	$ 5.2	$ 7.4	$ 6.0
Compensation expense									$ (2.1)	$ 10.9	$ (2.0)
EBITDA hurdle achieved of target	69.00%
2014 Incentive Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock, vested									176,994	152,328	160,553
Number of restricted stock vested for which shares issued									91,694
Number of restricted stock vested but deferred for issuance									80,800
2014 Incentive Plan \| RSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period									3 years
2014 Incentive Plan \| RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period									5 years
2014 Incentive Plan \| RSUs \| Executives and non-executive members of management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense									$ 1.5	$ 2.2	$ 5.0
2010 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred RSU's	180,000								180,000
2004 Stock Plan \| Converted from Restricted Stock Awards to Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares converted from RSAs to RSUs outstanding (in shares)												225,000
2004 Stock Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares converted from RSAs to RSUs outstanding (in shares)	29,945								29,945
Converted RSUs delivered (in shares)									195,055