Summary of Significant Accounting Policies - Debt Issuance Costs (Details) - USD ($) $ in Thousands	Jul. 31, 2020	May 31, 2020	Jul. 31, 2019
Accounting Policies [Abstract]
Net debt issuance costs	$ 11,166		$ 2,149
Debt issuance costs, unamortized		$ 4,365
Equity component of debt issuance costs		$ 1,377
Debt issuance costs, net	$ 4,246

Debt Issuance Costs, Gross, Equity Component

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

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

+ 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
-Subparagraph (SX 210.5-02.17)
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-Section 45
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
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-Publisher FASB
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