Stock-Based Awards - RSU's and Performance RSU's (Details) - $ / shares	3 Months Ended	9 Months Ended
Jan. 25, 2020	Oct. 26, 2019
Target Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Beginning balance (in shares)	474,508
Ending balance (in shares)		474,508
RSUs
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Beginning balance (in shares)	207,473	126,470
Granted (in shares)		115,973
Share units vested (in shares)		(34,384)
Forfeited or canceled (in shares)		(586)
Ending balance (in shares)		207,473
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)	$ 66.82	$ 87.92
Granted (in dollars per shares)		48.36
Share units vested (in dollars per shares)		82.17
Forfeited or canceled (in dollars per shares)		67.88
Ending balance (in dollars per shares)		$ 66.82
Performance RSUs
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Beginning balance (in shares)	667,583	377,354
Granted (in shares)		475,629
Share units vested (in shares)		(56,731)
Forfeited or canceled (in shares)		(128,669)
Ending balance (in shares)		667,583
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)	$ 64.68	$ 96.51
Granted (in dollars per shares)		45.94
Share units vested (in dollars per shares)		72.35
Forfeited or canceled (in dollars per shares)		85.38
Ending balance (in dollars per shares)		$ 64.68
Supplemental Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Outstanding [Roll Forward]
Beginning balance (in shares)	193,075
Granted (in shares)		142,062
Ending balance (in shares)		193,075
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)	(58,114)
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)	(33,068)

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=109197908&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
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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
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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

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-Publisher FASB
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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
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-Topic 718
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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- 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
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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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-Publisher FASB
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