Income Taxes - Components of Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
May 31, 2018	May 31, 2017	May 31, 2016
Income tax expense for continuing operations consists of the following components:
Federal	$ 137,601	$ 187,134	$ 272,663
State and local	19,582	27,197	25,428
Foreign	15,103	6,996	6,471
Current income tax expense	172,286	221,327	304,562
Deferred	(115,217)	8,791	(47,852)
Income taxes	$ 57,069	$ 230,118	$ 256,710

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

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Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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