Intangibles (Details) - USD ($) $ in Thousands	6 Months Ended
Oct. 28, 2017	Apr. 30, 2017
Intangibles
Intangibles, gross	$ 1,582	$ 2,481
Less accumulated amortization	(816)	(658)
Intangibles, net	766	1,823
Impairment charge	(899)
Licenses
Intangibles
Intangibles, gross	818	818
Customer relationships
Intangibles
Intangibles, gross	733	1,600
Impairment charge	(867)
Trademarks and tradenames
Intangibles
Intangibles, gross	28	60
Impairment charge	(32)
Other
Intangibles
Intangibles, gross	$ 3	$ 3

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

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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- 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.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

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