Income Taxes - Reconciliation from United States Statutory Federal Income Tax Rate to Effective Income Tax Rate (Detail)	12 Months Ended
	May 31, 2019	May 31, 2018	May 31, 2017
Income Tax Disclosure [Abstract]
Federal income tax rate	21.00%	29.20%	35.00%
State taxes, net of federal benefit	1.20%	1.20%	1.10%
Foreign earnings	(2.10%)	(17.50%)	(20.70%)
Transition tax related to the Tax Act	0.00%	43.30%	0.00%
Remeasurement of deferred tax assets and liabilities related to the Tax Act	0.00%	3.70%	0.00%
Excess tax benefits from share-based compensation	(3.60%)	(5.30%)	0.00%
Resolution of a U.S. tax matter	0.00%	0.00%	(3.20%)
U.S. Research and Development tax credit	(1.10%)	(0.60%)	(0.60%)
Other, net	0.70%	1.30%	1.60%
EFFECTIVE INCOME TAX RATE	16.10%	55.30%	13.20%