End date of current fiscal year in the format --MM-DD.

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- Definition

This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

+ References

No definition available.

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- Definition

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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No definition available.

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Award Annual Vesting Percentage

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested Shares Yet to be Awarded

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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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Shareholders' Equity - Schedule of Restricted Stock Awards and Restricted Stock Units by Grant Year and Vesting Period (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Apr. 28, 2018	Apr. 29, 2017	Apr. 30, 2016	Apr. 28, 2012	May 01, 2011	May 02, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Document Fiscal Year Focus	2018
Document Period End Date	Apr. 28, 2018
Current Fiscal Year End Date	--04-28
2010 Stock Plan \| RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded (in shares)	0	0	0	100,000	320,000
Number of Shares Unvested (in shares)	0	0	33,334			66,667
Annual vesting percentage	33.30%				20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested Shares Yet to be Awarded	210,000
2014 Incentive Plan \| RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded (in shares)	152,738	99,000	1,185,000
Number of Shares Unvested (in shares)	1,171,238	1,168,500	1,161,000			0
2014 Incentive Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded (in shares)	30,925	32,000	576,000
Number of Shares Unvested (in shares)	382,372	568,000	576,000			0
Weighted Average Value (in dollars per share)	$ 35.85
Unearned compensation expense	$ 5.1
2014 Incentive Plan \| RSUs \| Target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned compensation expense	$ 5.1
Threshold Performance \| 2014 Incentive Plan \| RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Unvested (in shares)	363,413
Weighted Average Value (in dollars per share)	$ 34.11
Unearned compensation expense	$ 5.5
Threshold Performance \| 2014 Incentive Plan \| RSAs \| Target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned compensation expense	$ 11.0