GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Jan. 28, 2017	Apr. 30, 2016
Finite-lived Intangible Assets [Roll Forward]
Gross	$ 42.2	$ 42.2
Accumulated Amortization	35.0	33.3
Net	7.2	8.9
Customer relationships and agreements
Finite-lived Intangible Assets [Roll Forward]
Gross	16.3	16.3
Accumulated Amortization	15.5	15.3
Net	$ 0.8	$ 1.0
Wtd. Avg. Remaining Amortization Periods (Years)	7 years 9 days	7 years 9 months 15 days
Trade names, patents and technology licenses
Finite-lived Intangible Assets [Roll Forward]
Gross	$ 25.8	$ 25.8
Accumulated Amortization	19.4	17.9
Net	$ 6.4	$ 7.9
Wtd. Avg. Remaining Amortization Periods (Years)	1 year 8 months 9 days	2 years 4 months 21 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)	8 months	1 year 5 months

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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- Definition

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+ References

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