Stock-Based Awards - RSU's and Performance RSU's (Details) - $ / shares	3 Months Ended
Jul. 25, 2020	Apr. 25, 2020
Target Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Beginning balance (in shares)	318,438
Ending balance (in shares)		318,438
RSUs
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Beginning balance (in shares)	647,839	174,917
Granted (in shares)		510,211
Share units vested (in shares)		(33,791)
Forfeited or canceled (in shares)		(3,498)
Ending balance (in shares)		647,839
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value [Roll Forward]
Beginning balance (in dollars per shares)	$ 33.75	$ 65.05
Granted (in dollars per shares)		25.20
Share units vested (in dollars per shares)		63.61
Forfeited or canceled (in dollars per shares)		63.37
Ending balance (in dollars per shares)		$ 33.75
Performance RSUs
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Beginning balance (in shares)	474,644	639,738
Granted (in shares)		65,538
Share units vested (in shares)		(12,315)
Forfeited or canceled (in shares)		(218,317)
Ending balance (in shares)		474,644
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value [Roll Forward]
Beginning balance (in dollars per shares)	$ 56.68	$ 62.60
Granted (in dollars per shares)		25.15
Share units vested (in dollars per shares)		64.27
Forfeited or canceled (in dollars per shares)		64.13
Ending balance (in dollars per shares)		$ 56.68
Supplemental Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Beginning balance (in shares)	156,206
Granted (in shares)		32,769
Ending balance (in shares)		156,206
Scenario, Forecast [Member] \| Performance RSUs
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Forfeited or canceled (in shares)	(143,954)
Scenario, Forecast [Member] \| Supplemental Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Forfeited or canceled (in shares)	(65,354)

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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- 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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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

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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

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
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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

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-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.

+ References

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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
-Topic 718
-SubTopic 10
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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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+ References

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