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Earnings Per Share - Reconciliation of Shares Used in Computation of Basic and Diluted Earnings Per Common Share (Parenthetical) (Detail)	May 31, 2021	Apr. 30, 2021	May 31, 2020
2.875% Convertible Notes Due 2024
Earnings Per Share Disclosure [Line Items]
Debt instrument, interest rate	2.875%	2.875%	2.875%
2.875% Convertible Notes Due 2028
Earnings Per Share Disclosure [Line Items]
Debt instrument, interest rate	2.875%
2.25% Convertible Notes Due 2024
Earnings Per Share Disclosure [Line Items]
Debt instrument, interest rate	2.25%	2.25%	2.25%

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- Definition

Earnings Per Share Disclosure [Line Items]

+ References

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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
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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