Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2019	Nov. 30, 2018
Income Tax Disclosure [Abstract]
Effective income tax expense rate	24.00%	26.20%	24.80%	24.70%
Corporate income tax rate			21.00%
Deferred income tax liability	$ 18,800,000		$ 18,800,000
Unremitted foreign earnings	414,700,000		414,700,000
Provision for deferred income taxes	$ 0		$ 0

Corporate income tax rate.

No definition available.

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- Definition

Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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Amount of deferred tax liability not recognized because of the exceptions to comprehensive recognition of deferred taxes related to undistributed earnings of foreign subsidiaries.

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- Definition

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

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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