Organization, Basis of Presentation, and Summary of Significant Accounting Policies - Debt Issuance Cost (Details) - USD ($) $ in Millions	Feb. 28, 2021	May 31, 2020
Debt Instrument [Line Items]
Current portion	$ 1.3	$ 0.4
Noncurrent portion	5.0	0.6
Prepaid Expenses and Other Current Assets
Debt Instrument [Line Items]
Debt issuance costs	0.6	0.3
Other Assets
Debt Instrument [Line Items]
Debt issuance costs	$ 2.3	$ 0.5

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Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section S45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68176171&loc=SL68176184-208336

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Amount, after accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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