Fair Value of Financial Instruments - Textuals (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 31, 2020	Apr. 30, 2019
Debt Instrument [Line Items]
Impairment of the operating lease assets, net of tax	$ 19.4
Level 3
Debt Instrument [Line Items]
Impairment of the operating lease assets, net of tax	$ 20.0
ASC 842
Debt Instrument [Line Items]
Impairment of the operating lease assets, net of tax		$ 9.6
LVMH Note
Debt Instrument [Line Items]
Debt instrument interest rate	2.00%
Debt Instrument, Face Amount	$ 125.0
Debt discount	$ 40.0

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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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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Amount, after accumulated amortization, of debt discount.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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- Definition

Amount of loss from impairment of right-of-use asset from operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 25
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=121593497&loc=SL77918431-209957

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