Increasing or Decreasing Current Health Care Cost Trend (Detail) - Postretirement Benefits - USD ($) $ in Thousands	12 Months Ended
May 31, 2018	May 31, 2017
U.S. Plans
1% Increase (Decrease) in healthcare cost trend rate
1% Increase in trend rate, accumulated benefit obligation	$ 185	$ 229
1% Increase in trend rate, postretirement cost	7	9
1% Decrease in trend rate, accumulated benefit obligation	(163)	(201)
1% Decrease in trend rate, postretirement cost	(6)	(8)
Non-U.S. Plans
1% Increase (Decrease) in healthcare cost trend rate
1% Increase in trend rate, accumulated benefit obligation	6,978	6,410
1% Increase in trend rate, postretirement cost	673	547
1% Decrease in trend rate, accumulated benefit obligation	(5,391)	(5,016)
1% Decrease in trend rate, postretirement cost	$ (493)	$ (406)

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- Definition

Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (m)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate.

+ References

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Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate.

+ References

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+ References

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