Income Taxes - Components of Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2019	May 31, 2018	May 31, 2017
Income tax expense for continuing operations consists of the following components:
Federal	$ 134,174	$ 124,861	$ 184,130
State and local	40,949	32,322	30,201
Foreign	9,882	15,103	6,996
Current income tax expense	185,005	172,286	221,327
Deferred	34,759	(115,217)	8,791
Income taxes	$ 219,764	$ 57,069	$ 230,118