Revenue Recognition, Contracts with Customers, Assets Recognized for the Costs to Fulfill a Contract (Details) - USD ($) $ in Thousands	3 Months Ended
Jul. 31, 2021	Jul. 31, 2020	Apr. 30, 2021
Assets Recognized for the Costs to Obtain or Fulfill a Contract [Abstract]
Costs capitalized	$ 11,800		$ 12,100
Amortization	1,500	$ 1,200
Cost of revenue [Abstract]
Operating and administrative expenses	260,589	237,369
Shipping and Handling [Member]
Cost of revenue [Abstract]
Operating and administrative expenses	$ 6,800	$ 6,700

No definition available.

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123353750&loc=SL49131252-203054

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123353750&loc=SL49131252-203054

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- References

No definition available.

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- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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