Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
May 31, 2016	May 31, 2015	May 31, 2014
Income Taxes [Line Items]
Interest and penalties	$ 0	$ 0
Effective tax rate	38.60%	37.40%	37.30%
Valuation allowance	$ 681	$ 398	$ 254
Undistributed Earnings of Foreign Subsidiaries	7,322	$ 7,574	$ 6,303
Undistributed earnings of foreign subsidiaries, cash	$ 5,702
United States federal jurisdiction
Income Taxes [Line Items]
Jurisdiction	years through fiscal 2011
State jurisdictions
Income Taxes [Line Items]
Jurisdiction	through fiscal 2004 and 2005

Income Taxes [Line Items]

No definition available.

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- Definition

Undistributed Earnings of Foreign Subsidiaries, Cash

+ References

No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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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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A brief description of status of the tax examination, significant findings to date, and the entity's position with respect to the findings.

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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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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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