Changes in Carrying Amount of Goodwill, by Reportable Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
May 31, 2017	May 31, 2016
Goodwill [Line Items]
Goodwill beginning balance	$ 1,219,630	$ 1,215,688
Acquisitions	75,361	29,762
Impairments	(141,394)
Translation adjustments	(9,684)	(25,820)
Goodwill ending balance	1,143,913	1,219,630
Industrial Segment
Goodwill [Line Items]
Goodwill beginning balance	475,409	476,700
Acquisitions	41,268	18,834
Translation adjustments	(342)	(20,125)
Goodwill ending balance	516,335	475,409
Specialty Segment
Goodwill [Line Items]
Goodwill beginning balance	171,714	165,934
Acquisitions	3,273	7,168
Translation adjustments	(1,009)	(1,388)
Goodwill ending balance	173,978	171,714
Consumer Segment
Goodwill [Line Items]
Goodwill beginning balance	572,507	573,054
Acquisitions	30,820	3,760
Impairments	(141,394)
Translation adjustments	(8,333)	(4,307)
Goodwill ending balance	$ 453,600	$ 572,507

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
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-Section 50
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