Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Oct. 26, 2019	Apr. 27, 2019
Indefinite-lived Intangible Assets [Line Items]
Gross	$ 1.8	$ 1.8
Net	1.8	1.8
Finite-lived Intangible Assets [Roll Forward]
Gross	320.4	320.0
Accumulated Amortization	66.4	56.9
Net / Total	254.0	263.1
Intangible assets, gross	322.2	321.8
Intangible assets, net	255.8	264.9
Trade Names, Patents and Technology Licenses
Indefinite-lived Intangible Assets [Line Items]
Gross	1.8	1.8
Net	1.8	1.8
Customer Relationships and Agreements
Finite-lived Intangible Assets [Roll Forward]
Gross	244.8	244.5
Accumulated Amortization	34.3	27.7
Net / Total	$ 210.5	$ 216.8
Wtd. Avg. Remaining Amortization Periods (Years)	17 years	17 years 4 months 24 days
Trade Names, Patents and Technology Licenses
Finite-lived Intangible Assets [Roll Forward]
Gross	$ 75.6	$ 75.5
Accumulated Amortization	32.1	29.2
Net / Total	$ 43.5	$ 46.3
Wtd. Avg. Remaining Amortization Periods (Years)	7 years 10 months 24 days	8 years 4 months 24 days

Finite-Lived Intangible Assets, Weighted Average Remaining Amortization Period

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- Definition

Indefinite-lived Intangible Assets (Excluding Goodwill), Gross

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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-Publisher FASB
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-Section 50
-Paragraph 2
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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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

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.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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