Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	9 Months Ended
Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Income Tax Disclosure [Abstract]
Effective income tax expense rate	31.10%	25.90%	25.20%	24.90%
Corporate income tax rate	21.00%	21.00%	21.00%	21.00%
Net of favorable discrete tax increase to deferred income tax liability withholding taxes on additional unremitted foreign earnings	$ 5,300,000		$ 5,300,000
Deferred income tax liability	17,700,000		17,700,000
Unremitted foreign earnings	620,700,000		620,700,000
Provision for deferred income taxes	$ 0		$ 0

Corporate income tax rate.

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- Definition

Net of favorable discrete tax adjustment of increase to deferred income tax liability for withholding taxes on additional unremitted foreign earnings.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 6
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Paragraph 2
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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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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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