Note A - Organization and Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, € in Millions	12 Months Ended
Jun. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2017 EUR (€) shares
Foreign Currency Contract, Asset, Fair Value Disclosure	$ 521,000	$ 250,000
Royalty and Licensing Revenue	26,900,000	21,800,000
Royalty Expense	1,000,000	865,000
Research and Development Expense	1,600,000	1,100,000
Advertising Expense	598,000	334,000
Liability for Uncertainty in Income Taxes, 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	$ 0
Concentration of Risk Number of Major Customers	3
Impairment of Long-Lived Assets to be Disposed of	$ 0	$ 0
Accounts Receivable [Member] \| Customer Concentration Risk [Member]
Concentration Risk, Percentage	65.60%	58.70%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Beta Alanine Raw Material Sale Customers [Member]
Concentration Risk, Percentage	21.30%	14.60%
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
2009 Omnibus Stock Incentive Plan [Member] \| Board of Directors and Management Members [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross \| shares	155,000	208,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares	0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number \| shares	319,335	193,012	319,335
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 2,500,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 146 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	$ 8.82	$ 9.86
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	$ 8.82
Foreign Exchange Contract [Member]
Derivative, Notional Amount	$ 26,100,000		€ 23.1
Derivative, Remaining Maturity	1 year 60 days
Minimum [Member]
Property, Plant and Equipment, Useful Life	1 year
Minimum [Member] \| 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
Maximum [Member]
Property, Plant and Equipment, Useful Life	39 years
Maximum [Member] \| 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	5 years
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

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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