GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Jan. 27, 2018	Apr. 29, 2017
Finite-lived Intangible Assets [Roll Forward]
Gross	$ 104.8	$ 42.2
Accumulated Amortization	39.2	35.6
Net	65.6	6.6
Customer Relationships and Agreements
Finite-lived Intangible Assets [Roll Forward]
Gross	66.5	16.3
Accumulated Amortization	17.2	15.6
Net	$ 49.3	$ 0.7
Wtd. Avg. Remaining Amortization Periods (Years)	12 years 11 months 15 days	6 years 9 months 18 days
Trade Names, Patents and Technology Licenses
Finite-lived Intangible Assets [Roll Forward]
Gross	$ 38.3	$ 25.8
Accumulated Amortization	22.0	19.9
Net	$ 16.3	$ 5.9
Wtd. Avg. Remaining Amortization Periods (Years)	5 years 6 months 12 days	1 year 4 months 24 days
Covenants Not to Compete
Finite-lived Intangible Assets [Roll Forward]
Gross		$ 0.1
Accumulated Amortization		0.1
Net		$ 0.0
Wtd. Avg. Remaining Amortization Periods (Years)		4 months 24 days

Finite-Lived Intangible Assets, Weighted Average Remaining Amortization Period

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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.

+ References

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

+ References

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+ References

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