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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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-Name Accounting Standards Codification
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-Paragraph 2
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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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-Publisher FASB
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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of valuation reserve for inventory.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

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-Glossary Financing Activities
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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No definition available.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Threshold period past due for trade accounts receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Significant Accounting Policies (Details) - USD ($)	3 Months Ended		6 Months Ended
Significant Accounting Policies (Details) - USD ($)	Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2016	Nov. 30, 2015	May 31, 2016
Significant Accounting Policies (Details) [Line Items]
Threshold Period Past Due for Write-off of Trade Accounts Receivable			90 days
Inventory Valuation Reserves	$ 42,000		$ 42,000		$ 52,000
Depreciation, Depletion and Amortization	37,501	$ 38,709	74,472	$ 78,860
Amortization of Intangible Assets	$ 20,515	$ 18,813	36,522	37,536
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit (in Dollars per share)	$ 0.43
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit (in Dollars per share)	$ 0.71
Proceeds from Stock Options Exercised	$ 57,000		56,556	$ 10,298
Deferred Tax Assets, Valuation Allowance	$ 1,122,000		$ 1,122,000		$ 1,038,000
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in Shares)	710,242	321,669	716,995	401,914
Investment In Polish Distributor [Member]
Significant Accounting Policies (Details) [Line Items]
Equity Method Investment, Ownership Percentage	6.00%		6.00%
Minimum [Member]
Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Maximum [Member]
Significant Accounting Policies (Details) [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Maximum [Member] \| Marketing-Related Intangible Assets [Member]
Significant Accounting Policies (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	18 years
Maximum [Member] \| Purchased Technology Rights [Member]
Significant Accounting Policies (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Maximum [Member] \| Patents [Member]
Significant Accounting Policies (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	17 years