Income Taxes - Reconciliation of Unrecognized Tax Benefits (Detail) $ in Thousands	12 Months Ended
May 31, 2018 USD ($)
Income Tax Disclosure [Abstract]
Beginning Balance	$ 2,975
Decreases - tax positions taken in prior years	(107)
Increases - tax positions taken in prior years	81
Increases - current tax positions	12
Settlements	(184)
Lapse of statutes of limitations	(139)
Ending Balance	$ 2,638

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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