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Note A - Organization and Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, € in Millions |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 19, 2015 shares | Mar. 07, 2014 shares | Jul. 01, 2013 USD ($) | Jun. 01, 2013 USD ($) | Dec. 01, 2012 USD ($) | Oct. 03, 2012 USD ($) | Jul. 12, 2012 USD ($) | Mar. 13, 2012 USD ($) | Mar. 31, 2014 USD ($) | Mar. 31, 2012 USD ($) | Jan. 31, 2012 USD ($) | Jun. 30, 2011 USD ($) | Sep. 30, 2013 shares | Jun. 30, 2015 USD ($) $ / shares shares | Jun. 30, 2014 USD ($) $ / shares shares | Jun. 30, 2013 shares | Jun. 30, 2015 EUR (€) shares | Jun. 30, 2015 USD ($) shares | Dec. 01, 2013 USD ($)
Amendment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from License Fees Received |  |  | $ 150,000 | $ 204,167 | $ 204,167 |  | $ 354,167 | $ 354,167 |  |  |  |  |  |  |  |  |  |  |
Additional License Fees Upon Achievement of Certain Milestones |  |  |  |  |  |  |  |  | $ 2,800,000 |  |  |  |  |  |  |  |  |  |
Additional License Fees Receivable Upon Achievement of Certain Milestones |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 150,000
Prior to Amendment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional License Fees Upon Achievement of Certain Milestones |  |  |  |  |  |  |  |  |  | $ 4,300,000 |  |  |  |  |  |  |  |  |
Additional License Fees Receivable Upon Achievement of Certain Milestones |  |  |  |  |  |  |  |  |  | $ 708,334 |  |  |  |  |  |  |  |  |
Installment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Installment Payments |  |  |  |  |  |  |  |  | 4 | 6 |  |  |  |  |  |  |  |  |
Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Net Asset (Liability) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |
Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Net Asset (Liability) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  |  |  |  |  |  |  |  |  |  |  |  | 39 years |  |  |  |  |
Foreign Exchange Contract [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative, Notional Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | € 23.8 | $ 27,100,000 |
Derivative, Remaining Maturity |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year 60 days |  |  |  |  |
Employee Stock Option [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% |  |  |  |  |
Restricted Stock [Member] | 2009 Omnibus Stock Incentive Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 105,000 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period | shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.51 |  |  |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 29,720 |  | 93,866 | 93,866 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 945,000 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.51 | $ 5.56 |  |  |  |
2009 Omnibus Stock Incentive Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares | 105,000 | 105,000 |  |  |  |  |  |  |  |  |  |  |  |  |  | 98,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | 3 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3 years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period | shares |  |  |  |  |  |  |  |  |  |  |  |  | 10,000 |  |  |  |  |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Beta Alanine Raw Material Sale Customers [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  | 26.00% |  |  |  |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | CSI [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 23.60% |  |  |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  | 28.50% | 26.90% |  |  |  |
Proceeds from License Fees Received |  |  |  |  |  | $ 150,000 |  |  |  |  | $ 300,000 | $ 300,000 |  |  |  |  |  |  |
Impairment of Long-Lived Assets to be Disposed of |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 417,000 | $ 0 |  |  |  |
Liability for Uncertain Tax Positions, Current |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  | 0 |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 193,000 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 121,000 |  |  |  |
Foreign Currency Contract, Asset, Fair Value Disclosure |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 474,000 |
Foreign Currency Contracts, Liability, Fair Value Disclosure |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 24,000 |  |  |  |
Royalty and Licensing Revenue |  |  |  |  |  |  |  |  |  |  |  |  |  | 9,100,000 | 5,400,000 |  |  |  |
Royalty Expense |  |  |  |  |  |  |  |  |  |  |  |  |  | 806,000 | 722,000 |  |  |  |
Research and Development Expense |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,100,000 | 1,000,000 |  |  |  |
Advertising Expense |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 69,000 | $ 131,000 |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 151,000 | 268,000 |  |  |  |
Concentration of Risk Number of Major Customers |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |

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