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Note A - Organization and Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, € in Millions |  | 12 Months Ended |
--- | --- | --- | ---
Mar. 19, 2015 shares | Jun. 30, 2016 USD ($) $ / shares shares | Jun. 30, 2015 USD ($) $ / shares shares | Jun. 30, 2016 EUR (€) shares | Jun. 30, 2016 USD ($) shares
Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair Value, Net Asset (Liability) |  |  | $ 0 |  | $ 0
Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair Value, Net Asset (Liability) |  |  | $ 0 |  | $ 0
Employee Stock Option [Member] |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares |  | 0 | 151,000 |  |
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] | Board of Directors and Management Members [Member] | Minimum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 0 years |  |  |
Restricted Stock [Member] | 2009 Omnibus Stock Incentive Plan [Member] | Board of Directors and Management Members [Member] | Maximum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 5 years |  |  |
Restricted Stock [Member] | 2009 Omnibus Stock Incentive Plan [Member] | Board of Directors and Management Members [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | 3 years |  |  |  |
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, Weighted Average Grant Date Fair Value | $ / shares |  | $ 9.86 |  |  |
Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | shares |  |  | 93,866 | 193,012 | 193,012
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options |  |  |  |  | $ 2,300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition |  | 1 year 219 days |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares |  | $ 9.86 | $ 5.51 |  |
2009 Omnibus Stock Incentive Plan [Member] | Board of Directors and Management Members [Member] |  |  |  |  |
Stock Issued During Period, Shares, Restricted Stock Award, Gross | shares | 105,000 | 208,000 |  |  |
2009 Omnibus Stock Incentive Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares |  |  |  |  |
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 |  |  |  | € 16.8 | 19,000,000
Derivative, Remaining Maturity |  | 1 year 60 days |  |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Beta Alanine Raw Material Sale Customers [Member] |  |  |  |  |
Concentration Risk, Percentage |  | 14.60% | 26.00% |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] |  |  |  |  |
Concentration Risk, Percentage |  | 61.10% | 25.80% |  |
Liability for Uncertainty in Income Taxes, Current |  |  | $ 0 |  | 0
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, Vested in Period, Fair Value |  | $ 0 | $ 0 |  |
Foreign Currency Contract, Asset, Fair Value Disclosure |  |  | 474,000 |  | $ 250,000
Impairment of Long-Lived Assets to be Disposed of |  | 0 | 417,000 |  |
Royalty and Licensing Revenue |  | 21,800,000 | 9,100,000 |  |
Royalty Expense |  | 865,000 | 806,000 |  |
Research and Development Expense |  | 1,100,000 | 1,100,000 |  |
Advertising Expense |  | 334,000 | $ 69,000 |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  | $ (193,000) |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares |  | 0 | 0 |  |
Concentration of Risk Number of Major Customers |  | 2 |  |  |

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