Stock-based Compensation - Restricted Stock Awards and Restricted Stock Units (Details) - 2014 Stock Plan $ / shares in Units, $ in Millions	6 Months Ended
Oct. 26, 2019 USD ($) $ / shares shares
RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EBITDA goal, percentage of likelihood	70.00%
RSAs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares earned range, percent	0.00%
RSAs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares earned range, percent	150.00%
RSAs \| Management
Wtd. Avg. Grant Date Fair Value
Non-vested and unissued, beginning balance (in dollars per share) \| $ / shares	$ 34.09
Awarded (in dollars per share) \| $ / shares	0
Vested (in dollars per share) \| $ / shares	33.78
Forfeited (in dollars per share) \| $ / shares	33.78
Non-vested and unissued, ending balance (in dollars per share) \| $ / shares	$ 34.10
Allocated share-based compensation expense, amount recorded to true-up prior periods \| $	$ 7.4
RSAs \| Management \| 2020 EBITDA Maximum Performance
Shares
Non-vested and unissued, beginning balance (in shares) \| shares	1,031,408
Awarded (in shares) \| shares	0
Vested (in shares) \| shares	(11,250)
Forfeited (in shares) \| shares	(5,670)
Non-vested and unissued, ending balance (in shares) \| shares	1,014,488
RSUs
Shares
Non-vested and unissued, beginning balance (in shares) \| shares	187,844
Awarded (in shares) \| shares	0
Vested (in shares) \| shares	(4,500)
Forfeited (in shares) \| shares	0
Non-vested and unissued, ending balance (in shares) \| shares	183,344
Wtd. Avg. Grant Date Fair Value
Non-vested and unissued, beginning balance (in dollars per share) \| $ / shares	$ 34.55
Awarded (in dollars per share) \| $ / shares	0
Vested (in dollars per share) \| $ / shares	33.78
Forfeited (in dollars per share) \| $ / shares	0
Non-vested and unissued, ending balance (in dollars per share) \| $ / shares	$ 34.57
RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years

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

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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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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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Percentage of vesting of share-based compensation awards.

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