Fair Value and Carrying Value of Financial Instruments and Long-Term Debt (Detail) - USD ($) $ in Thousands	Nov. 30, 2021	May 31, 2021
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 192,851	$ 246,704
Marketable equity securities	143,412	142,087
Available-for-sale debt securities	26,904	26,745
Long-term debt, including current portion	2,465,993	2,379,826
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	192,851	246,704
Marketable equity securities	143,412	142,087
Available-for-sale debt securities	26,904	26,745
Long-term debt, including current portion	$ 2,713,027	$ 2,570,206

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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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.

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