v2.4.0.6

Segment Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Aug. 31, 2012		Aug. 31, 2011		May 31, 2012
Segment Reporting Information [Line Items]
Net sales to external customers	$ 49,729		$ 45,697
Operating income (reduction)	10,328		9,350
Total assets	260,797		227,622		251,600
Food Safety
Segment Reporting Information [Line Items]
Net sales to external customers	26,195		23,282
Operating income (reduction)	7,669		7,163
Total assets	89,170		68,689
Animal Safety
Segment Reporting Information [Line Items]
Net sales to external customers	23,534		22,415
Operating income (reduction)	3,243		2,743
Total assets	105,769		98,231
Corporate Eliminations
Segment Reporting Information [Line Items]
Net sales to external customers	0	[1]	0	[1]
Operating income (reduction)	(584)	[1]	(556)	[1]
Total assets	$ 65,858	[1]	$ 60,702	[1]
[1] Includes corporate assets, consisting principally of cash and cash equivalents, marketable securities, deferred assets and overhead expenses not allocated to specific business segments. Also includes the elimination of intersegment transactions.

X

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Concepts (CON)

-Number 6

-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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X

- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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X

- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-03.1)

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