Shareholders' Equity and Share-Based Compensation - Nonvested Restricted Stock and RSU Activity (Details) - Restricted Stock and Restricted Stock Units - $ / shares shares in Thousands	12 Months Ended
May 02, 2020	Apr. 27, 2019	Apr. 28, 2018
Number of Nonvested Shares
Outstanding at beginning of year, Nonvested Shares	444	437	402
Granted, Nonvested Shares	186	181	178
Vested, Nonvested Shares	(173)	(169)	(141)
Forfeited, Nonvested Shares	(8)	(5)	(2)
Outstanding at end of year, Nonvested Shares	449	444	437
Weighted Average Grant Date Fair Value Per Share
Outstanding at beginning of year, Weighted Average Grant Date Fair Value (usd per share)	$ 7.58	$ 8.48	$ 8.69
Granted, Weighted Average Grant Date Fair Value (usd per share)	7.03	6.79	8.46
Vested, Weighted Average Grant Date Fair Value (usd per share)	8.10	9.05	9.06
Forfeited, Weighted Average Grant Date Fair Value (usd per share)	7.37	7.74	8.93
Outstanding at end of year, Weighted Average Grant Date Fair Value (usd per share)	$ 7.16	$ 7.58	$ 8.48

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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.

+ References

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-Publisher FASB
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-Topic 718
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-Section 50
-Paragraph 2
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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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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).

+ References

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-Publisher FASB
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-Topic 718
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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-Publisher FASB
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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