Fair Value Measurements (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2015	May 31, 2014
Assets
Supplemental executive retirement plan	$ 3,500	$ 3,418
Fair Value, Measurements, Recurring
Assets
Total assets measured at fair value	3,500	3,427
Foreign exchange forward contracts	4
Fair Value, Measurements, Recurring \| Money market funds \| Supplemental executive retirement plan
Assets
Supplemental executive retirement plan	166	323
Fair Value, Measurements, Recurring \| Mutual funds \| Supplemental executive retirement plan
Assets
Supplemental executive retirement plan	3,334	3,095
Fair Value, Measurements, Recurring \| Foreign exchange forward contracts
Assets
Foreign exchange forward contracts		9
Foreign exchange forward contracts	4
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring
Assets
Total assets measured at fair value	3,500	3,418
Foreign exchange forward contracts	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring \| Money market funds \| Supplemental executive retirement plan
Assets
Supplemental executive retirement plan	166	323
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring \| Mutual funds \| Supplemental executive retirement plan
Assets
Supplemental executive retirement plan	3,334	3,095
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring \| Foreign exchange forward contracts
Assets
Foreign exchange forward contracts	0
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets
Total assets measured at fair value	0	9
Foreign exchange forward contracts	4
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Foreign exchange forward contracts
Assets
Foreign exchange forward contracts		9
Foreign exchange forward contracts	$ 4

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

No definition available.

+ Details

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- Definition

+ References

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative liabilities not designated as hedging instruments.

+ References

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