Goodwill - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
Apr. 30, 2020	Apr. 30, 2021	Apr. 30, 2020	Apr. 30, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Accumulated goodwill impairment charges		$ 109,300,000
Goodwill gross		173,600,000
Impairment of goodwill	$ 98,900,000	$ 0	$ 98,929,000	$ 10,396,000

No definition available.

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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