Intangibles (Schedule of Intangible Assets) (Details) - USD ($) $ in Thousands	Jul. 31, 2020	Apr. 30, 2020
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangibles, gross	$ 274,000	$ 274,000
Less accumulated amortization	(117,972)	(106,556)
Intangibles, net	156,028	167,444
Trademarks
Finite-Lived Intangible Assets [Line Items]
Intangibles, gross	10,000	10,000
Less accumulated amortization	(8,611)	(7,778)
Intangibles, net	$ 1,389	$ 2,222

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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