8. PRODUCT WARRANTIES (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at the beginning of the period	$ 219	$ 168	$ 137	$ 223
Accruals for warranties issued during the period	128	66	237	98
Settlement made during the period (in cash or in kind)	(42)	(85)	(69)	(172)
Balance at the end of the period	$ 305	$ 149	$ 305	$ 149

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(5))
-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

+ References

+ Details

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- Definition

Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.

+ References

+ Details

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