Increasing or Decreasing Current Health Care Cost Trend (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
May 31, 2014	May 31, 2013
Postretirement Benefits, U.S. Plans
Assumed Health Care Cost Trend Rates, Effect of One Percentage Point Change [Line Items]
1% Increase in trend rate, accumulated benefit obligation	$ 239	$ 296
1% Increase in trend rate, postretirement cost	11	15
1% Decrease in trend rate, accumulated benefit obligation	(209)	(265)
1% Decrease in trend rate, postretirement cost	(10)	(13)
Postretirement Benefits, Non-U.S. Plans
Assumed Health Care Cost Trend Rates, Effect of One Percentage Point Change [Line Items]
1% Increase in trend rate, accumulated benefit obligation	6,502	9,080
1% Increase in trend rate, postretirement cost	727	647
1% Decrease in trend rate, accumulated benefit obligation	(5,011)	(3,802)
1% Decrease in trend rate, postretirement cost	$ (534)	$ (481)

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (m)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

+ Details

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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