Consolidated Statements of Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
May 31, 2021	May 31, 2020	May 31, 2019
Income Statement [Abstract]
Discontinued operations, income tax (benefit) expense	$ 0	$ (107)	$ 757

Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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+ Details