Long-term Incentive Plans (Narrative) (Detail)	12 Months Ended
May 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Incentive stock options, term	10 years
Shares of stock initially reserved for issuance under long-term incentive plan	500,000

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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