Summary of Significant Accounting Policies - Computation of Basic and Diluted Earnings Per Share (Details) - shares shares in Thousands	12 Months Ended
Apr. 25, 2020	Apr. 27, 2019	Apr. 28, 2018
Earnings Per Share [Abstract]
Denominator for basic earnings per share – weighted average shares (in shares)	94,154	92,755	92,467
Effect of dilutive securities – stock options, restricted stock and stock purchase plans (in shares)	0	729	627
Diluted (in shares)	94,154	93,484	93,094
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	2,517	1,792	1,380

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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