Amortizable of Intangible Assets (Detail) - USD ($) $ in Thousands	May 31, 2017	May 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 85,395	$ 74,162
Less Accumulated Amortization	30,777	24,807
Net Carrying Amount	54,618	49,355
Licenses
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	5,989	5,189
Less Accumulated Amortization	2,011	1,782
Net Carrying Amount	3,978	3,407
Noncompete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,208	491
Less Accumulated Amortization	309	193
Net Carrying Amount	899	298
Patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9,304	8,040
Less Accumulated Amortization	4,601	3,631
Net Carrying Amount	4,703	4,409
Customer-based intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	56,829	48,186
Less Accumulated Amortization	20,846	17,277
Net Carrying Amount	35,983	30,909
Other products and service-related intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	12,065	12,256
Less Accumulated Amortization	3,010	1,924
Net Carrying Amount	$ 9,055	$ 10,332

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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