Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 31, 2021	Jul. 31, 2020
Income Tax Disclosure [Abstract]
Income tax expense	$ 0.4	$ 0.1

Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32639-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Name:	us-gaap_CurrentIncomeTaxExpenseBenefit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration