Income Taxes - Components of Income Tax Expense (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2018	May 31, 2017	May 31, 2016
Current
Federal	$ 33,261	$ 50,200	$ 42,837
State and local	3,292	2,954	2,157
Foreign	9,904	7,593	6,639
Current Income Tax Expense (Benefit), Total	46,457	60,747	51,633
Deferred
Federal	(34,442)	18,177	7,584
State and local	388	476	934
Foreign	(4,183)	(210)	(1,164)
Provision for (benefit from) deferred income taxes	(38,237)	18,443	7,354
Income tax expense	$ 8,220	$ 79,190	$ 58,987