Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	Feb. 29, 2020	Feb. 28, 2019
Income Tax Disclosure [Abstract]
Effective income tax expense rate	25.90%	224.70%	24.90%	17.80%
Corporate income tax rate	21.00%	21.00%	21.00%	21.00%
Net favorable discrete tax	$ 300,000
Net of favorable discrete tax increase to deferred income tax liability withholding taxes on additional unremitted foreign earnings	10,900,000
Favorable impact of net discrete tax benefits on relatively low level of pre-tax earnings		$ (12,700,000)		$ (12,700,000)
Discrete tax expense (benefit)		$ (8,100,000)		$ (16,500,000)
Deferred income tax liability	29,700,000		$ 29,700,000
Unremitted foreign earnings	631,900,000		631,900,000
Provision for deferred income taxes	$ 0		$ 0