GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
Jul. 27, 2017	Jul. 29, 2017	Apr. 29, 2017
Finite-lived Intangible Assets [Roll Forward]
Gross		$ 54.2	$ 42.2
Accumulated Amortization		36.1	35.6
Net		18.1	6.6
Customer Relationships and Agreements
Finite-lived Intangible Assets [Roll Forward]
Gross		28.3	16.3
Accumulated Amortization		15.6	15.6
Net		$ 12.7	$ 0.7
Wtd. Avg. Remaining Amortization Periods (Years)		9 years 9 months 21 days	6 years 9 months 18 days
Trade Names, Patents and Technology Licenses
Finite-lived Intangible Assets [Roll Forward]
Gross		$ 25.8	$ 25.8
Accumulated Amortization		20.4	19.9
Net		$ 5.4	$ 5.9
Wtd. Avg. Remaining Amortization Periods (Years)		1 year 2 months 27 days	1 year 4 months 24 days
Covenants Not to Compete
Finite-lived Intangible Assets [Roll Forward]
Gross		$ 0.1	$ 0.1
Accumulated Amortization		0.1	0.1
Net		$ 0.0	$ 0.0
Wtd. Avg. Remaining Amortization Periods (Years)		2 months	4 months 24 days
Procoplast
Finite-Lived Intangible Assets [Line Items]
Intangible Assets Acquired	$ 12.0
Procoplast \| Customer Relationships and Agreements
Finite-Lived Intangible Assets [Line Items]
Amortization period	10 years

Finite-Lived Intangible Assets, Weighted Average Remaining Amortization Period

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=73531372&loc=d3e2207-128464

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

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

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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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No definition available.

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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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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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